Two antenna questions
Unrevealed Source
Alpha Delta switch, model Delta 4? Since the Daiwa CS-401 is discontinued
and seemingly impossible to find, I'm looking to upgrade from 2 to four
positions (more radios) but don't want the cheap junk of MFJ. Is there
another good but reasonably priced 4-port switch that anyone has experience
with, or do you recommend the Alpha Delta? That one is $75. This is for
receive only.
2) What do you do if you have succesfully matched your longwire to a 50ohm
coax with a MLB and have coax coming into the house, but now want to use
that on a high-impedance antenna input (those radios that don't have a coax
connection but just a terminal or jack for a long wire)? Do you do another
MLB with just a short length of wire on the antenna side for connection to
the radio?
Thanks in advance for any informative responses.
Not a question, but some obvervations: Just got two new radios. First was
a Sony ICF-5900W (thanks Mike!). Excellent working condition and very
solid. After giving it a good bath (alcohol, toothbrush, Q-tips, etc) and
then some Novus, and of course making sure the innards were clean and lubed,
it works like a charm and looks almost brand new. Very sensitive radio. I
was most impressed by the audio clarity. Side by side with the RF-2200 I
might have to give the edge to the Sony, for just voice clarity.
Second new radio was a Panasonic RF-5000A. I have always wanted one but
they go for too much and those that don't are generally pretty banged up.
Got an eBay Second-Chance offer and lucked out. Amazingly well-preserved.
Did a similar but more involved cleaning, and was a little intimidated at
first when I opened it up. Have you ever seen the inside of one of these?
Definitely the most well-built radio that I have ever seen, and once I sat
down and took my time it was actually easy to dissassemble. After a
thorough cleaning and reassembly, it looks like new. Literally. And it
works great. There is no doubt that it is, as most say, the best sounding
portable ever. This is one BIG and HEAVY radio. Shortwave seems to be
pretty sensitive, but I haven't put it through any serious head-to-head
comparisons. This may be my new "Best of Show", based on condition and just
how cool it is. If you ever have a chance to pick one of these up, you'll
love it.
David
<unreveal...@nospam.com> wrote:
>1) Does anyone have any experience with or recommend an alternative to an
>Alpha Delta switch, model Delta 4? Since the Daiwa CS-401 is discontinued
>and seemingly impossible to find, I'm looking to upgrade from 2 to four
>positions (more radios) but don't want the cheap junk of MFJ. Is there
>another good but reasonably priced 4-port switch that anyone has experience
>with, or do you recommend the Alpha Delta? That one is $75. This is for
>receive only.
>
>2) What do you do if you have succesfully matched your longwire to a 50ohm
>coax with a MLB and have coax coming into the house, but now want to use
>that on a high-impedance antenna input (those radios that don't have a coax
>connection but just a terminal or jack for a long wire)? Do you do another
>MLB with just a short length of wire on the antenna side for connection to
>the radio?
>
Low Z generators are allowed into Medium Z inputs.
You cannot feed a Low Zinput with a Higher Z generator
Think of Impedance ''Z'' as the diameter of a pipe.
Telamon
"Unrevealed Source" <unreveal...@nospam.com> wrote:
> 1) Does anyone have any experience with or recommend an alternative to an
> Alpha Delta switch, model Delta 4? Since the Daiwa CS-401 is discontinued
> and seemingly impossible to find, I'm looking to upgrade from 2 to four
> positions (more radios) but don't want the cheap junk of MFJ. Is there
> another good but reasonably priced 4-port switch that anyone has experience
> with, or do you recommend the Alpha Delta? That one is $75. This is for
> receive only.
Try the radio swap groups or amateur news groups.
> 2) What do you do if you have succesfully matched your longwire to a 50ohm
> coax with a MLB and have coax coming into the house, but now want to use
> that on a high-impedance antenna input (those radios that don't have a coax
> connection but just a terminal or jack for a long wire)? Do you do another
> MLB with just a short length of wire on the antenna side for connection to
> the radio?
This post may not be much help but that said using another MLB in
reverse from low to high impedance is at least theoretically correct.
Practically though you might be better off using a single insulated wire
from the long wire to the radio high impedance input as long as house
local noise is not an issue.
--
Telamon
Ventura, California
Bob Miller
<unreveal...@nospam.com> wrote:
>1) Does anyone have any experience with or recommend an alternative to an
>Alpha Delta switch, model Delta 4? Since the Daiwa CS-401 is discontinued
>and seemingly impossible to find, I'm looking to upgrade from 2 to four
>positions (more radios) but don't want the cheap junk of MFJ. Is there
>another good but reasonably priced 4-port switch that anyone has experience
>with, or do you recommend the Alpha Delta? That one is $75. This is for
>receive only.
Alpha Delta has four position switches. See their web site. Or try the
Ameritron web site for really heavy duty.
bob
k5qwg
James
is why he wants it.
---------------------------------------------
Unrevealed Source
for/against and possible alternatives.
"James" <jnipp...@nospamfdn.com> wrote in message
news:vamdnbX8W6C0FfLZ...@comcast.com...
David
For receiving a Cable TV type switch works fine.
RHF
The "Alpha Delta" - Delta 2 and Delta 4 Antenna Switches
are still listed at Universal Radio
http://www.universal-radio.com/catalog/switch/2415.html
http://www.universal-radio.com/catalog/switch/2415alt.gif
http://www.universal-radio.com/catalog/switch/0011.html
FWIW - I like the design lay-out and the solid build
quality {Feel} of the Alpha Delta Antenna Switches.
[ Having all the Coax Connectors on one side ]
Daiwa Antenna Switches are also listed at Universal Radio
http://www.universal-radio.com/catalog/switch/1864.html
List of Antenna Switches at Universal Radio
http://www.universal-radio.com/catalog/switch.html
Also check
* Amateur Electronics {Equipment} Supply (AES)
AES HAM => http://www.aesham.com/
* Ham Radio Outlet (HRO)
HRO => http://www.hamradio.com/
For the 'used' Antenna Switches : Why not check eBay
on a Weekly basis to see what might come along.
* Search eBay for [ antenna + switch ]
in Category : Radios : CB, Ham & Shortwave
ANTENNA SWITCH => http://tinyurl.com/nx4pz
For "Receive Only" Low-Power {No Power} Use
even a TV type Antenna Switch could work with
the right Adapters. Also some of the CB quality
Antenna Switches with SO-239 Jacks will do.
eHAM Reviews for Category : Antenna Switches
http://www.eham.net/reviews/products/2
# 2 - Yes - Antenna -to- MLB -to- Coax Cable
-to- MLB -to- Radio - Works !
hope this helps - iane ~ RHF
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Unrevealed Source
Are you implying that you've actually used an Antenna -to- MLB -to- Coax
Cable -to- MLB -to- Radio setup?
"RHF" <rhf-new...@pacbell.net> wrote in message
news:1148353100....@g10g2000cwb.googlegroups.com...
David
<unreveal...@nospam.com> wrote:
>It does help, thank.
>
>Are you implying that you've actually used an Antenna -to- MLB -to- Coax
>Cable -to- MLB -to- Radio setup?
Not necessary.
RHF
Antenna -to- MLB -to- Coax Cable -to- MLB -to- Radio
[ TV Antenna -to- MT -to- Coax Cable -to- MT -to- TV ]
http://groups.yahoo.com/group/Shortwave-SWL-Antenna/message/9692
Actually this was quite common with many old TV Sets
and Roof-Top Off-the-Air Antennas.
TV Matching Transformer leads connected across the
two sides of the TV Antenna. Coax Cable from the
Antenna down to the TV Set. Matching Transformer
between the Coax Cable and TV Set. This arangement
usually gave better TV Reception then plain old 300 Ohm
Twin Lead with fewer Ghosts. - Many Old TV sets did not
have an "F" Connector Antenna Input.
Back to Shortwave Listening Antennas :
Yes - I have constructed and build a few types of
Shortwave Listening (SWL) Antenna using simple
TV type Parts and used the common TV type Matching
Transformer at the Antenna to Coax Cable connection
and at the Coax Cable to Radio connection.
TV type Parts List :
300 Ohm to 75 Ohm Matching Transformers
300 Ohm Twin Lead
75 Ohm Coax Cable
300 Ohm Terminals to 75 Ohm 1/8" Plug Matching Transformers
1/8" Plug
Hook-Up Wire
Speaker Wire
Landscaping Cable
Shortwave Listening Antennas made from TV type Parts :
* Dipole Antenna using Hook-Up Wire.
* T2FD Antenna using Twin Lead.
* Windom Antenna using Twin Lead.
* Inverted "V" Antenna using Hook-Up Wire.
* Sloper Antenna using Hook-Up Wire.
* Loop Antenna using Twin Lead.
* Fence-Top Horizontal [Flat] Random Wire Antenna
using Landscaping Cable.
For most Shortwave Receivers that have a Pair of
HI-Z 500 Ohm Terminals the 75 Ohm "F" Connector
to 300 Ohm Two Lead Matching Transformer works OK.
For most 'portable' AM / FM Shortwave Radios that
have a 1/8" Mono-Jack as the External Antenna Input.
Connecting an 1/8" Mono-Plug to the Leads of the
300 Ohm side of a 75 Ohm "F" Connector to 300 Ohm
Two Lead Matching Transformer works OK.
For a Second - Shortwave Listening (SWL) Antenna :
If you already have a good Shortwave Listening (SWL)
Antenna connected to the SO-239 Jack of your Receiver :
Then you may wish to consider a simple Windom
Antenna made completely of 300 Ohm TV type Twin Lead
or 450 Ohm Ladder Line as a second HI-Z Antenna
to use with your Receiver's HI-Z Antenna Inputs.
This type of "Windom" is an Off-Center Fed Folded Dipole.
Some people like to have the Down Lead Section
{feed-in-line} lay Flat {untwisted}; while I like mine
Twisted. Starting with a 100 Foot piece of Twin-Lead
or Ladder-Line a Windom Antenna cut for the 49m
and 31m Bands would be :
Tip-to-Tip 63.0 Feet
Long Arm Side of 38.5 Feet (1/4 WL 49m)
Short Arm Side of 24.5 Feet (1/4 WL 31m)
Vertical Down Lead of 17.1 Feet {Mounting Height}
with the rest used for feed-in-line to the Receiver.
find some wire and locate some space
- next build and antenna - iane ~ RHF
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