[G4DDK] Back to the Nacton

[G4DDK via rec.radio.amateur.moderated Admin]

G4DDK- A radio blog

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Back to the Nacton

Posted: 21 Jan 2014 01:01 PM PST
http://g4ddk.blogspot.com/2014/01/back-to-nacton.html

I have spent much of the last few days, after returning from Heelweg,
making measurements on Nacton 2m transverters. John, G4SWX, has identified
some problems with the original filter designs and advised on some
improvements. These in turn showed up some other areas for improvement
including the diode switch in the receive path between the RF front end and
the band pass filter. It looks like new switching diodes are in order!

Initial measurements with the new filters and an alternative PIN diode show
a big improvement in dynamic range.

John has also provided some new and possibly better post mixer amplifier
devices. I will be trying one of these devices over the next few days,
together with some other changes.

IF all this works, as it should, then the result could be an outstanding
performance from a small, low cost, 144/28MHz transverter.

One further item of news. The scaffolding, that has prevented my use of the
2.3m dish, has been removed as next door's extension comes towards
completion. At last I can get back on 23cm EME. Weather permitting of
course.......!


Sam




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Location:The shack

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ZLPLL

Posted: 14 Jan 2014 04:00 AM PST
http://g4ddk.blogspot.com/2014/01/zlpll.html





I recently ordered a ZLPLL from Wayne, ZL2BKC, in New Zealand.
This is a ADF4351 based source board, capable of generating a signal
between 31 and 4400MHz from an on-board 26MHz OCXO or external 10MHz
reference. Wayne supplies a detailed manual for the ZLPLL, in PDF format,
on his web page. ZL2BKC.com

The ZLPLL turned up, safely, in this morning's post.

I wanted the ZLPLL to use with my 144MHz Nacton transverter, to be used
where carrier stability was important, such as with digital modes like
JT65B and when onward transverting to the microwave bands, where the LO of
the transverter would also be locked to the shack 10MHz standard (GPS or
Rubidium). This ZLPLL has already been programmed for me to give a
(switchable) 116 or 115MHz output.

The Nacton 2m has provision for an external 116MHz input, if required.
On initial inspection the ZLPLL looks excellent.

I will probably give it a proper set of tests ( especially to check if it
meets my phase noise needs) after this coming weekend's Heelweg trip is
over. Right now I'm still getting things ready to take to the meeting.

My thanks to Wayne for his prompt attention to my order and congratulations
on a fine piece of kit.

Sam



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K3 update

Posted: 09 Jan 2014 01:39 PM PST
http://g4ddk.blogspot.com/2014/01/k3-update.html

Last May, at the Dayton Hamfest I bought a few 'accessories' for my K3. I
was keen to try the bigger screen available by adding an SVGAP3 adapter to
my P3. This meant updating the K3 +12v output via the switchable phono
socket on the back of the rig. The parts to do this ( updated polyfuse and
bigger choke) were provided with the SVGAP3 card. However, I had not got
round to fitting these parts as I still hadn't ( still haven't!) fitted the
SVGAP3 card inside the P3. There is a good reason for this, but I won't
bore you with it now. That's for another blog.
Last week I received a PR6-10 preamp to increase the sensitivity of the K3
on these two bands. This preamp is also powered from the same +12v output
as the P3 and whilst there was probably enough to power these two items, I
wanted to add the SVGAP3 card soon, so decided to do the mod to the +12v
supply.
This turned out to be a bit more involved than I expected, necessitating
removing the top and bottom covers and the 100W PA. After that it was quite
straightforward!
Whilst I had the covers off I thought I would fit the other accessory I'd
bought at Dayton. The general coverage BPF. Again, more dismantling. The
KBPF3 fits on top of the K3 ham band filter bank, but it necessitates
removing the internal 2m transverter.
With the transverter removed the KBPF3 fitted easily.

With everything back together it all seemed to work OK, so the next job is
to fit the SVGAP3 card in the P3 and see it it works as it should.

More about the preamp and results as well as how the SVGA
3 works in a later blog when I've had a chance to test the preamp and
fitted the P3 card.

Sam



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Dayton

Posted: 02 Jan 2014 09:36 AM PST
http://g4ddk.blogspot.com/2014/01/dayton.html

I'm not sure how I missed Dayton off my list of events attended last year!

This was far more a social event for me than one where I go to buy a rig or
accessories. Having said that I did buy some bits for my Elecraft K3 inc.
an SVGA card for the P3 display and the general coverage filter card.
To add to that I have a 10/6m preamp somewhere in transit from the USA, as
a Christmas present to myself. Where oh where is it?!!!!!!!!!according to
USPS it reached the UK on the 27th December, so maybe tomorrow.

I spent some time with Lloyd, NE8I, at Dayton. Lloyd was taken seriously
Ill shortly after he got back home to Michigan. I'm pleased I did spend
that time with him as he is unlikely to attend Dayton again, anytime soon.
Get well, Lloyd.

I did blog about my Dayton trip in an earlier blog on here, if you really
want to read more! Really?.........

Sam





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10Ghz update

Posted: 15 Dec 2013 08:57 AM PST
http://g4ddk.blogspot.com/2013/12/10ghz-update.html

Taking a break from my 4m and 2m transverter kit work I thought that I
would see what I could do with my 10GHz transverter system, having been
goaded into doing something by G4BAO's constant prodding!!!

I have not been QRV on 10GHz for over a year and had actually sold my
original 10W transverter in lieu of using a smaller and marginally lighter
8W transverter that I had obtained in the meantime. Unfortunately the DB6NT
PA in that transverter had 'expired' and I didn't particularly want to
replace the 8W FET as the cost was felt to be a bit excessive.

After putting the transverter on one side for the summer I recently started
to think about 10GHz again, with more goading by John.

A few weeks ago I inquired about my old transverter and was delighted to
find that I could buy it back from its new owner as it didn't meet their
needs for various reasons.

Today I took a look at what needed to be done to restore the transverter to
full working condition. Although it had been pretty badly 'mauled' it looks
like it can be restored to working condition. In particular the original
DB6NT G2 transverter module had suffered from low transmit output. With
the 'new' transverter module out of the defunct 8W transverter it should be
possible to get back to a full 10W output.

I managed to find the original 10GHz transverter paperwork ( written
exactly 11 years ago today!) and I think that I can work from that to get
it all working again. It looks like I have a Christmas project.

If all goes well I hope to report on further progress on the 10GHz in the
next few weeks.

Sam





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Catch up

Posted: 15 Dec 2013 08:23 AM PST
http://g4ddk.blogspot.com/2013/12/catch-up.html

I have had a few weeks break from my blog. I was unable to blog whilst on
holiday and got out of the habit!

Since getting back I have distributed quite a few of the 4m band Nacton
transverter short kits, but I've now got back to testing the 2m version (
144MHz RF to 28MHz IF).

Today I tested this version and it seems to be living up to expectations.
The noise figure is less (better) than the 4m version and gain is slightly
better ( expected because of the performance of the RF front end MMIC).
I have made a few small changes to the circuit to improve performance and
these will probably be reflected back into the 4m version.

I have arranged for a couple of 2m versions of the Nacton to be built up
by some of my friends in order to test their reproducibility.

If this further testing goes well I will make kits available, as for the 4m
version. I haven't decided how much of the kit will be available and how
much you will need to source yourself.

G4FRE is currently testing a 472kHz version of the Nacton. It uses the same
PCB as the VHF transverters, but a few different components and lots of
different values........

BTW, the name Nacton is taken from the local village near to where the
Codgers radio group hold our monthly Saturday breakfast meeting.
Just in case you wondered!


Sam


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Location:Falkenham Road,Kirton,United Kingdom

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Apologies

Posted: 29 Nov 2013 01:29 PM PST
http://g4ddk.blogspot.com/2013/11/apologies.html

I have not blogged as promised during my trip down under, but I was
thwarted by Google.
As my Nexus blog is linked to my gmail account Google decided that my
access from NZ was possibly fraudulent and blocked my posts. I had to
verify it was actually me. So far so good. But I didn't have access to my
password. Attempts to reset using Google's system don't work when you don't
have cellular coverage....
I gave up in frustration.
Yes, thank you, I had a great holiday!
Sam


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More storms

Posted: 02 Nov 2013 03:14 PM PDT
http://g4ddk.blogspot.com/2013/11/more-storms.html

After Monday's storm I thought that was it. Today it started blowing again
and my son happened to mention that a dead elm tree on the edge of our
property was leaning precariously towards the lane at the side of our
property. Rather than leaving it to fall on a passing car it was out with
the bow saw and then with a good deal of sawing, cutting of ivy with the
branch loppers, and it was finally in two large pieces; ready to heave away
and dispose of.

What is the radio connection? It just about missed my 40m dipole that had
been collapsed down to protect it from the storm on Monday. It seems
nowhere is safe from storm damage.

Sam




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Location:Falkenham Road,Kirton,United Kingdom

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Hacked

Posted: 31 Oct 2013 07:26 AM PDT
http://g4ddk.blogspot.com/2013/10/hacked.html

It seems that my e-mail was hacked on Thursday evening and my contact
address list stolen. Just about everyone on the list was then e-mailed by
the hacker with a sob story that I was mugged or something in Manila and
needed money. I sincerely hope none of you were taken in by this very
common scam?
I must have seen it at least six times in the last two years. The wording
in the e-mail should have been a real give away. It was clearly not written
by a native English speaker. It is too flowery and imprecise.

The first thing these hackers do when they get access to your account is
change your own password so that you can't get back into your mail and make
your own changes. You must contact your own ISP and get them to clear the
hack. You can then change the password.
However, it may not end there. I was informed that some of my messages were
being forwarded to the hacker. What had happened was that they had gone
into the personal security area of my account and substituted another
e-mail address in place of the second account you have previously entered.
From this point on any messages received from the ISP will be copied to the
hacker! Clever.......
Make sure you also run a virus checker over your PC or WHY and look for
Trojans or key loggers that might have been embedded in your system.
I have also changed my passwords on all my accounts and groups
and even more than once on my e-mail.

Don't EVER click on a link in an e-mail, however innocent it may
appear.......

I have no idea if I have really cleared the hacker out of my system, but
since doing all this I have been constantly bombard with more phishing
e-mails and realistic looking postings 'from' BT to upgrade my e-mail
client etc. it all looks like someone trying to find their way back in.
Needless to say I am even more wary of anything received that looks out of
the ordinary. I'm not sure whether being without internet access for 52
hours after the storm has helped or not.

Sam




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Power outages

Posted: 31 Oct 2013 07:05 AM PDT
http://g4ddk.blogspot.com/2013/10/power-outages.html

Following the St Jude's day storm we were without power for 52 hours. Power
came back on at mid day on Wednesday.
That was long enough to destroy a freezer and fridge/freezer's worth of
food........
As happens my standby sealed lead acid battery was not charged and even my
iPhone battery was low on charge. It was only possible to use my phone by
taking the iPhone for a ride in the car to get some juice back into it!
Of course, there was no amateur radio activity during this period.
We relied on a cheap and cheerful transistor radio to listen to Radio
Suffolk and obtain storm progress and power restoration reports. I am not
sure that a battery powered DAB radio battery would have lasted the full 52
hours. There is a lot to be said for simple AM and FM radio!
We registered for text updates from UK Power Networks. Although texts were
forthcoming they were of very limited use. Even a rough indiction of when
power might have been restored would have been useful. I know that it may
have been hard with a widespread outage, but changed reports such as 'it's
an overhead fault' followed by 'it's a substation fault' are clearly made
up as it changed back to overhead again when more engineers were deployed
to our fault. Such messages serve to annoy rather than re-assure the
customer that the problem is being dealt with. Come on, UKPN, acknowledge
that web pages are not necessarily very useful when power is off and texts
need to be more informative. A proper national radio information emergency
channel ( possibly on FM) would be useful at disseminating useful
information. The internet is NOT the ideal information channel at these
times.

Thanks to the loan of a small generator by one of the local amateurs we
were able to power a light for one evening, but not much else.
The lesson learnt from all this is that we need our own generator and a
switch unit to isolate the house from incoming mains so that the generator
can be plugged in to power some of the house items at least.

Sam





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Location:Falkenham Road,Kirton,United Kingdom

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OFCOM visit

Posted: 24 Oct 2013 01:20 PM PDT
http://g4ddk.blogspot.com/2013/10/ofcom-visit.html

Today I was part of the RSGB team that met with OFCOM in London.
My role was to present EME in a favourable light, as part of the Space
exhibit and one of the four areas of amateur radio on show today. The other
ares were home construction, working pile-ups & ARDF, and a table-top
antenna test range.
This was a follow-up to another technical meeting, held earlier this year.
These meetings are in addition to the regular administrative meetings
between RSGB and OFCOM.

With the amateur radio license terms and conditions consultation coming up
next year, these meetings are essential to a successful future for our
hobby.

During the meeting I met the OFCOM staff responsible for the 2.3 and 3.4GHz
Consultation. That consultation is still ongoing. We have to wait to hear
the eventual outcome.
However, I was able to explain first hand, to relevant OFCOM staff, some of
the issues (of possible changes) for EME enthusiasts and what EME was
capable of achieving given an interference free channel on these two
important EME bands.

One of the presentation slides has an embedded video showing G3LTF working
W5LUA using SSB on the 13cm amateur band ( video courtesy of BATC) . I
could see that OFCOM staff were impressed that we were able to do this at
all, given the great path losses involved and the limitations of our
amateur license.

I have come away from the meeting with a very favourable impression of the
OFCOM staff involved in amateur radio licensing, their understanding of our
position and sure that they do care about us and will do their very best to
ensure we retain a 13cm and 9cm allocation for EME and probably other areas
of amateur interest.

It was also clear that the other exhibits and presenters did a good job,
from the candid comments I overheard.

We should be thankful that the RSGB have engaged so effectively with OFCOM
and that is good for the hobby's future.

As an aside I was surprised to hear one the OFCOM staff refer to our
aircraft scatter activities whilst we were chatting over lunch. Following
an explanation of what was involved, the distances that could be covered,
etc the person appeared very impressed with what we have been able to
achieve.
I would judge it was a very successful day and I am pleased I was asked to
participate.

Sam




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Convention preparations

Posted: 11 Oct 2013 10:04 AM PDT
http://g4ddk.blogspot.com/2013/10/convention-preparations.html

Getting ready to go to the RSGB Convention tomorrow.
My bags of kits are packed, my talk is ready and my contest entry is
finished at last.
Hope to see you in the Raleigh Room at 17:00, immediately after John'
G4SWX,s talk on Remote Station Operation. I will be describing my 70MHz
transverter.
Anyone wanting to buy a VLNA kit needs to catch me early as I am only
taking a few for sale. I,ll also have a few PGA and SPF Amp kits for sale.
Find me on the UKuG stand.73 de Sam
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Hamfest

Posted: 30 Sep 2013 01:49 PM PDT
http://g4ddk.blogspot.com/2013/09/hamfest_30.html

I went to Newark on Friday.
A very enjoyable day out. I had volunteered to spend some of the day on the
RSGB PSC stand although I was also able to spend a little time with Roger
Banks on The DX Shop stand. There seemed to be a lot of interest in his
new Gemini 4 70MHz PA and Roger was kept busy answering questions about the
new 300W solid state power amplifier. Roger had a few of my built VLNA low
noise preamps for sale on the stand, hence my interest.
Back on the PSC stand there was a steady flow of visitors. The PSC stand
was in the block of stands allocated to the RSGB and was just across the
way from the main RSGB stand. This obviously had its benefits as we were
able to direct some of our visitors across to the main stand in order to
re-new subscriptions, buy books or just meet members of the RSGB board.
Steve, G0KYA, is the Chairman of PSC. He had set up the PSC stand the
previous day and it featured a number of photos, diagrams and a laptop
running a slide show. Of particular interest was the plot of sun activity
through this cycle. Steve didn't think we had reached the peak of this
cycle just yet as the sun's magnetic field didn't seem to have flipped.
My only purchase of the day was a Cross Country Wireless SDR4+
This was purchased as a lowish cost way to produce a panoramic display on
my TS2000. As the SDR4 frequency coverage has been increased to 4m it is
now also capable of covering the first IF of the TS2000.
I struggled through Saturday to get it to work on my W7PRo desktop, but
without success. I couldn't get the Si570 tuning to work.
On Sunday I tried again, but the installation was now onto my W7pro laptop.
This time I was successful, but then I found the SDR-Radio software
wouldn't apparently work at 70MHz!
I've put the SDR on one side for now and turned my attention back to
preparations for the RSGB Convention in 12 days time.
I'm expecting a batch of PCBs this week. When I have these I will build one
up to produce a 4m transverter to prove the PCB and to give me another
version of the Nacton to photograph for the Convention!
73 de Sam
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Location:Falkenham Road,Kirton,United Kingdom

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Hamfest

Posted: 26 Sep 2013 02:01 PM PDT
http://g4ddk.blogspot.com/2013/09/hamfest.html

Off to the Newark Hamfest tomorrow. I will be spending some time on the
RSGB PSC stand as well as a bit of time on The DX Shop stand.

I will be looking for another SDR to use as a panadapter with my TS2000.
More on what I find, if anything, when I get back.

I hope to see many microwavers at the 12o'clock get together near The DX
Shop stand.


Not looking forward to the early start tomorrow, though!

73 de Sam




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4m again

Posted: 22 Sep 2013 02:27 PM PDT
http://g4ddk.blogspot.com/2013/09/4m-again.html

I operated for an hour or so in the PW 4m contest this afternoon. I was
rather surprised when several stations said 'thanks for the new multiplier!'
Was I the only JO02 station on 4m today? Apparently not. There was at least
one more station on from somewhere north of me. I didn't hear them.

I used my original Nacton 4m transverter with the K3 and the external SSPA
at about 100W output to my 5 element dual band 6/4m YU7EF yagi.
The only propagation I observed was tropo, so ranges weren't so great and
there was lots of the usual slow QSB. My best DX was probably Tony, GW8ASD,
who I usually work on the microwave bands and who is usually many dB
stronger on 23cm than he was on 4m today,
As always, I found the waterfall and spectrum display on my P3 to be
invaluable for spotting activity and knowing where to tune without the
hassle of having to tune up and down the band.
4m.
73 de Sam
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Location:Home

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More 4m

Posted: 15 Sep 2013 02:07 PM PDT
http://g4ddk.blogspot.com/2013/09/more-4m.html

DUBUS turned up two days ago. Interesting that it contains a nice 4m
transverter design by DF4UE. What is surprising is how similar some of it
is to my Nacton design. Maybe I shouldn't be surprised at the similarities.
Anyone starting out to design a transverter today would probably choose to
use modern MMICs for the RF stages. Indeed DF4UE has chosen to use the same
MMIC for the RF stage. Even the mixer(s) are the same as used in the
Nacton, although I use just one whilst Johann uses two.

I have added more interface switching options since the original design.
When interfacing the original transverter module to the PA, external linear
etc it became obvious that it needed a few more options. I'll talk about
this at the Convention.

As I mentioned in my last blog I have spent a lot of time during the week
drawing the schematic circuit diagram using my PCB CAD package and then
modifying the PCB mask to correspond. Or maybe it was the schematic
modified to agree with the PCB?........
Anyway, both are now ready to be used in my Convention talk next month.

I've etched another couple of PCBs, using the latest mask, drilled them
and am now ready to assemble another transverter using some alternative
and easier to obtain parts to those in the early transverters. In
particular I have had to order a set of tuneable coils from Coilcraft.
Coilcraft are usually happy to supply free samples as long as you are not
too greedy. The chosen tuneable inductors are similar to the now-obsolete
TOKO parts used in the original design. I am keen to check that these ones
do fit the hole pattern in the PCB and have an adequate adjustment range to
cover the required 4m frequency range. I've been informed that the samples
have been dispatched and hopefully will arrive this week.
Dave, G4HUP, is currently stocking what appear to be suitable 42MHz third
overtone crystals in HC49U package, so I will be obtaining one of those
tomorrow in order to try it in the oscillator stage. The transverter has
facilities for an external LO input where the requirement for greater
stability warrants it.

If all goes well I plan on getting a small batch of PCBs made in the next
few weeks.
I might have these back from production before my talk in mid October.

The other thing I have been doing is working out how to assemble my 3cm
band EME RF feed unit. After weighing the successful 6cm EME unit I have
found that the 3cm power amplifier, waveguide switch, and adapter weighs in
some 1kg less, leaving just enough margin to add the mounting plate,
transverter and feed without exceeding the target weight of 4kg I have
arbitrarily set.
As my TVRO dish has a quadrapod feed support, meant to support a
lightweight Chaparal horn and LNB, it has limited ability to support a
heavy RF head. It will probably need further supports to prevent sag when
the dish is elevated.
As we approach the autumn equinox the sun is getting lower in the sky so
that sun noise testing time is reducing rapidly.
Sam
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Location:Home

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4m

Posted: 15 Sep 2013 01:12 PM PDT
http://g4ddk.blogspot.com/2013/09/4m.html

I have been busy updating the documentation for my Nacton 4m transverter
design, ready for my talk at the RSGB Convention, next month.
So far the design documentation has only existed as a series of notes in my
shack notebook and in my head!
The need to ensure I have a comprehensive circuit schematic and PCB design
ready for my talk means I have been having to critically examine all parts
of the original and has already resulted in a number of small changes.
Consequently I now need to produce another set of transverter hardware to
check out these changes.
The good thing in doing this is that, because there is a good deal of
commonality between the 70MHz Nacton and 144MHz Kirton transverters, I
should be able to document the Kirton much more rapidly.......
Sam
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Tek492P spectrum analyser

Posted: 31 Aug 2013 08:35 AM PDT
http://g4ddk.blogspot.com/2013/08/tek492p-spectrum-analyser.html

This is the TEK492P spectrum analyser I mentioned in my posting on the UK
Microwave Reflector.
With 18-26.5 and 26.5-40GHz external mixers and Diplexer
Analyser covers to 21GHz on its Coaxial input.




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Scotland

Posted: 16 Aug 2013 10:36 AM PDT
http://g4ddk.blogspot.com/2013/08/scotland.html

Following our recent trip to the Isle of Mull for a few days break and to
take up a long-standing invite to stay with friends on the island I have
returned determined to get the EME system back on air. More on this in
another posting.







First, Mull...... What a lovely place! Although we didn't see any eagles we
did see dolphins, otters, red deer, puffins, assorted other sea birds and
lots of herons.





Our trip across the island to Tobermory via Salen on a very narrow single
track road was exciting and definitely a great way to see more of the
island than many visitors see.





I am still enjoying the large piece of Mull Cheddar cheese bought at the
Tobermory cheese farm!

We had dinner at our friend's, friends sea food restaurant, the 'Ninth
Wave' near Fionafoort. Carla and John, the owners, did us proud. It was a
very special birthday meal for my XYL! Fresh caught Lobster, fine wine and
very tasty desert...........
The Ninth Wave, http://www.ninthwaverestaurant.co.uk/contact/
Highly recommended.

The following day we took the boat to Staffa and then Iona. It was from the
boat that we saw the puffins and then the dolphins. Unfortunately the
puffins had pretty much left the island by mid August, but were observable
at sea.




Fingals cave on Staffa




Dolphins feeding on the way back from Staffa

After a brief call back on Mull the boat took us across to Iona so that we
could see the abbey and have lunch. Then the regular ferry back to Mull.




Benedictine abbey on Iona. The original abbey, built by St Columba, has
been largely lost and the newer abbey built in its place. It's still worth
a visit.

We left for home with the regret that we didn't have longer to spend in
this fantastic place. I'm sure we will be back.







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Earthing the mast

Posted: 01 Aug 2013 12:53 PM PDT
http://g4ddk.blogspot.com/2013/08/earthing-mast.html

Today I decided to connect a protective earth ( ground) to my Versatower.
This mast has been up for 11 years next month and in all that time I have
not had a grounding system in place. I've relied on luffing the mast over
whenever there is a storm in the area.
After a long chat with G3NYK and G4HUP about this at our weekly coffee get
together last Sunday I decided I really had to do something.
Today was the day.



For now I am relying on a single ground rod. I will increase this to 2 or
three in the very near future.
What has been the problem up to now is deciding how to connect to the
metalwork of the tower. Although the round sections of the lattice would be
a convenient place to make a connection, the fact that the mast luffs over
means that a long ground lead would be required when new mast was puffed
over. That is not a good idea. The ground lead should be as short as
possible to ensure that the inductance of the lead is low. The rapid rise
time of lightning discharges do not want to encounter a lot of inductive
reactance.
I decided to drill a 9mm hole on one of the mast ground post
locating 'pegs' and fit an M9 stainless steel bolt that would hold the
ground lug on one end of the ground wire. These pegs are the nearest point
on the mast to the ground beyond the concrete base of the mast. The locking
pin prevents getting too close to the end of the peg, but near enough.
The photo shows two parallel ground wires. This is probably not a good idea
and a single, large diameter, or flat, non-braided, ground would be better
and will come later.
The ground rod is driven 4 foot into the (soft sand) and the big brass
clamp is secured to the ground wire lug with brass M8 stud and nuts.
The black 'gunk' is an RTV sealant to protect the lugs and screws as well
as the wire.


Sam



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G100RSGB

Posted: 27 Jul 2013 01:40 PM PDT
http://g4ddk.blogspot.com/2013/07/g100rsgb.html

Today was 'Last Saturday' so the Codgers had their monthly breakfast get
together at the Orwell Crossing Truck Stop. We had a good turnout, once
again, with around 35 in attendance. This monthly meeting was started some
6 1/2 years ago and has continued to be very popular with East Anglian
radio amateurs. It is very much an eclectic group, with interests varying
from LF through propagation, microwave and optical comms.
A large number of very well known and respected radio amateurs are members
of the Codgers group.


Codgers is not a radio club. It is just an informal group of radio amateurs
and radio interested persons.
If you are in the area on the last Saturday of any month, please join us at
10:00am at the Truck Stop. You will be very welcome.






After the Last Saturday Braekfast I joined the Felixstowe and District
Amateur Radio Society at nearby Foxhall Road, for a few hours, to take my
turn at operating G100RSGB. At 00:00GMT the G100RSGB call sign will be
passed on to the next group to hold it for two days.

Meanwhile Felixstowe club will continue tomorrow with a GB call sign at the
Foxhall road site. This is an old Cold War troposcatter station with three
tall towers which once proudly sported dishes and a flyswatter reflector.

Disused since about 1992, when the USAF moved out, it is now a museum and
hosts regular open days.

The radio club has used the site regularly for a number of years and as it
is in the middle of nowhere it is possible to run relatively high power on
HF without fear of causing interference to anyone.

The warm weather today meant a good turn out both from the public visiting
the Comms site museum and other attractions, and popping in to see the
radio club and what we were doing with all that wire in the air.....

The radios include K3 with linear, FT857, IC718 and some other radio that I
forgot to note!
The antennas include a G5RV, 3 element triband yagi, some sort of HF
vertical and yagis for 6,4,2 and 70cm

A very enjoyable few hours......
73 de Sam







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Some tests on 3cm

Posted: 25 Jul 2013 02:20 PM PDT
http://g4ddk.blogspot.com/2013/07/some-tests-on-3cm.html

I have been operating my Yaesu G1000DXC mast rotator remotely using an ERC
controller and PSTRotator Lite, over WiFI. I realised earlier this week
that I could also use PSTRotator to control my Spid Ras az/el rotator
remotely from the indoor shack.
With a bit of help from Cudrot, YO3DMU, the author of PSTRotator, I am now
able to use PSTRotator to control the dish and PSTRotator Az to control the
mast rotator.
With this capability in place I replaced the 23cm feed on my small EME dish
with a selection of 3cm antennas, using a 1.2m length of Suhner low loss
coax to the 3cm transverter, mounted on the rear of the dish.

This worked well, even over more than 70m of coax, to the shack 144MHz IF
rig.
But, I found it difficult to hold the dish on the sun in order to get a
meaningful sun noise to cold sky reading, although the less critical
pointing at the ground and then cold sky proved that the system was indeed
working and on some dish headings I could hear the nearby GB3MHX beacon
signal by scatter off local buildings and structures.

The principal reason for doing this was to see if the EME dish could be
used for rain scatter contacts.
My conclusion is that it can be done, but will be difficult because the
dish is so sharp.

On 6m I have continued to add locator squares to the few I already had when
I started this SpE season! I now have 163 locators and 49DXCC. Recent
additions have been a couple of USA stations, including Dave Orleans,
K1WHS, who I have met several times in the USA and from whom I have bought
a number of antennas ( he only recently sold Directive Systems).
This evening I worked a CU1 station ( thanks for the heads up, Graham).
Afterwards I was called by CT1DMK. Luis and I moved up the band and had a
long chat. It was his first contact on the band with his new log periodic
antenna and just 20W. As conditions on the SpE path began to deteriorate we
signed.
That is three new locators on the band today!

Coming back to 3cm. Today I was able to test a number of surplus 10GHz,
10W SSPAs that had been donated to our group. Each produced a comfortable
14W indicated output, at 10368MHz, and one ( a keeper!) did an indicated
18W output. These outputs were achieved for 8mW input. Nice!

73 de Sam


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Remote operation of the shack - update

Posted: 17 Jul 2013 10:55 AM PDT
http://g4ddk.blogspot.com/2013/07/remote-operation-of-shack-update.html

Several weeks ago I decided to buy an 8 channel ( relay) USB card to plug
into my shack PC. This PC is usually left on and by using LogMeIn I can
already access my rotator controller and log book, both on this PC, from my
indoor shack laptop. Now with the USB relay card I can remotely switch up
to 8 circuits on and off, with full isolation.

My current plan is to switch one of my remote linear amplifiers on and off
line and to switch one of my antennas to the common feeders. The other
channel uses are still being decided.

Although I bought the card several weeks ago it was only last night that I
got round to downloading the control application and trying it out. It
requires a USB connection to the PC and 12V to power he card. 24V versions
are also available as are cards with more channels.

I purchased the Bulgarian made Denkovi card from EBay at $41
With these cards you are permitted to download and use their own DRM
(Denkovi Relay Manager) v2.0 control application to switch the eight
channels on or off. The state of the relay is then signalled back to the
GUI. The name of the control channel can be labelled to reflect the
controlled function.

How does it work? I haven't connected the card to the linear or coax relay
yet, but I have had fun remotely turning LEDs on and off! It has been
extremely reliable so far.





Channels 2, 4, 6 and 8 all turned on.

Sam




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Progress

Posted: 15 Jul 2013 03:03 PM PDT
http://g4ddk.blogspot.com/2013/07/progress.html

I have not had too much of a chance to play radio in the last two weeks due
to decorating. However, I did get to visit the Finningley Microwave Round
Table on Sunday 15th. This is an annual event staged at the Finningley
radio club site at the old RAF Finningley site.
It is actually a two-day meeting but since I prefer not to stay overnight I
usually only get there on the Sunday. This year it was my turn to drive the
400 mile round trip with a 06:15 start from home and returning at 21:30. A
long day for me!
I attended several of the talks and also set up to sell some of my low
noise preamps as well as sell some of the remaining parts from the estate
of G4PBP.
Overall, I about covered costs, but that was secondary to being there.
My only purchases of the day were a couple of 144-160MHz high power Alcatel
(350W average, 2kW peak) circulators for £7 for the pair !

I also purchased a couple of old Aerial Facilities Ltd hybrid couplers for
the milled boxes and connectors. These will be stripped out and then turned
into diplexers( maybe triplexers) to enable me to combine and then split
two radios onto one cable passing through the shack wall and then to split
them again to feed an HF antenna and a dual band 2m/70cm antenna.

Don't forget to answer the 9 OFCOM questions on the 13 and 9cm consultation
web page!

Sam




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Friedrichschafen or, three men in a boat!

Posted: 03 Jul 2013 02:41 PM PDT
http://g4ddk.blogspot.com/2013/07/friedrichschafen-or-three-men-in-boat.html

Now that the dust has settled and I am recovered from the weekend's trip to
Friedrichschafen, the story can be told!






This was my fourth trip to FHN. For the second time I travelled by plane,
boat and train, arriving at Zurich airport on Thursday afternoon, taking
the Intercity train to Romanshorn and then the ferry across Lake Constance
(Bodensee) to the town of Friedrichschafen on the German ( northern) bank
of the lake.



Arriving into Friedrichschafen harbour


My travel companions were Graham, G4FSG and John, G4BAO.

We met up with a bunch of the Camb Hams on the ferry for the short crossing.





A drink on the ferry with the Camb Hams

After a great breakfast on Friday morning at the City Krone hotel, where we
were staying, it was off to the Messe on the free bus.
Since we had previously bought our tickets on line we were able to join the
shortish line to get into Hall1

I had some business to complete ( delivering VLNA preamps) on the Friday
morning, so it limited my time to look around until late morning.

Hall 1 houses all the clubs as well as the various traders selling 'new
stuff'. Traders like Kuehne Electronic, EISCH Electronic, Schubert
Electronic, the Icom, Yaesu and Kenwood stands together with lots of
smaller and larger traders selling everything from antennas to SDRs, RC
helicopters, QSLS cards and computer wares.

Between Halls A1 and Hall A, where the first of the flea market stands were
to be found, was the QSL wall, DARC presentation area, food court and A2
talks rooms.





Part of the QSL wall

I met up with Enrico, IW5BCE, at the QSLS wall at 1pm. this is an annual
event when all the EME ops get together to either arrange the evening's
meal or just meet and say hello in person. Enrico is the organiser for the
EME Friday evening meal event on Lindau Island ( on the lake).

After lunch of Curry Wurst and Pomme Frites, washed down with German beer,
it was on to the serious business of looking round the flea market stalls.

I have to admit I didn't buy a lot on the first day ( or the second!)

Being very tired and 'hammed out' we went back to the hotel about 5pm,
ready for the evening meal with the Camb Hams at a local Chinese-Indian
restaurant. To be honest the quality of service left a lot to be desired
and I doubt we will be going back there again.
However, the company of the Camb Hams more than made up for the long
serving delay and general quality of the food.

On day two it was a repeat of the trip to the Messe, followed by a good
scour of Hall A4 and then back to Hall A3. Undoubtedly the quality of
the 'items' in Hall A3 were superior, although this may be my perception as
a microwaver.

This was also the day when Chris Duckling, G3SVL, presented his talk on 100
years of the RSGB and its association with other societies. Earlier there
had been a talk on IOTA, also arranged by the RSGB.




Chris does his talk in one of the A2 convention rooms.

During the day I met up with a number of amateur radio friends from around
the world. One of these was Bruce, PY2BS! Visiting from Brazil with his
wife and son. in order to have more time to chat we arranged to meet up on
the lakefront in Friedrichschafen and have our evening meal together.

We (Graham, John and I) were joined by Bruce, XYL Darsheema and son Max.

Sitting in the restaurant, looking out across the lake at the falling rain
( yes, it rained on the Saturday....) but enjoying a superb Greek meal with
excellent wine made I seem like a different world!

Sunday morning and Graham and I elected to spend another few hours at the
Messe whilst John went off the visit the adjacent Zeppelin museum.




A Zeppelin flies over the Messe!

All to soon it was time to head off for the ferry and the train and plane.
But not before we had a last Kaffee und Kuchen, sitting by the lakefront.
Most enjoyable!

The trip home was uneventful and although we were all tired, we all felt it
was worth the expense.





John's friend says goodbye as we approached Romanshorn!




Arriving back in Romanshorn.

In all I didn't buy a great deal ( what do you buy a man who already has
everything?)!!!!!!!
I bought some adapters, attenuators and GaAs FETs and of course lots of
coffee, ice cream and the various meals and beer.

I was also presented with a nice 23cm feed for my EME dish. I want to thank
Carlos and Victor for the very kind thought. I will be testing it soon and
promise to report back on my results.

I'll be updating the Friedrichschafen blog as and when I think of anything
else to cover.

73 de Sam




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