Rigol Function Generators - experience?

[Joe Gwinn]

My Agilent 33220A function generator (bought in 2004) died yesterday,
so I need a replacement. (It's too old to bother with repair, and
it's time for a big upgrade anyway.)

I'm looking at a Rigol model DG1062Z. Any opinions and experience?

Joe Gwinn

[Spehro Pefhany]

On Tue, 06 Apr 2021 12:51:20 -0400, Joe Gwinn <joeg...@comcast.net>
wrote:

I have the DG4062 which is similar but 500M s/s sample rate rather
than 200.

Nice piece of kit. Gorgeous display.
--
Best regards,
Spehro Pefhany

[Joe Gwinn]

I was looking at that one too. It's very attractive.

But the arbitrary waveform memory is only 16 Kbytes (or samples?),
which won't last long at 500 Msamps/sec. Do they really mean 16 K, or
is the data sheet wrong?

The DG106Z samples at 200 or 25o Msamps/sec, and comes with 8 Mbytes
(or samples?) of memory.

Joe Gwinn

[George Herold]

I like my cheap DG1022. You can sync the two channels and adjust the phase.
George H.

[Spehro Pefhany]

On Tue, 06 Apr 2021 20:01:35 -0400, Joe Gwinn <joeg...@comcast.net>

wrote:

>On Tue, 06 Apr 2021 16:59:07 -0400, Spehro Pefhany
><spef...@interlogDOTyou.knowwhat> wrote:
>
>>On Tue, 06 Apr 2021 12:51:20 -0400, Joe Gwinn <joeg...@comcast.net>
>>wrote:
>>
>>>My Agilent 33220A function generator (bought in 2004) died yesterday,
>>>so I need a replacement. (It's too old to bother with repair, and
>>>it's time for a big upgrade anyway.)
>>>
>>>I'm looking at a Rigol model DG1062Z. Any opinions and experience?
>>>
>>>Joe Gwinn
>>
>>I have the DG4062 which is similar but 500M s/s sample rate rather
>>than 200.
>>
>>Nice piece of kit. Gorgeous display.
>
>I was looking at that one too. It's very attractive.
>
>But the arbitrary waveform memory is only 16 Kbytes (or samples?),
>which won't last long at 500 Msamps/sec. Do they really mean 16 K, or
>is the data sheet wrong?

It's correct but you can spread the (up to) 16K points over just about
any period of time up to 10^6s and it will linearly interpolate
between points if desired.

Manuals: https://www.rigolna.com/products/waveform-generators/dg4000/

>The DG106Z samples at 200 or 25o Msamps/sec, and comes with 8 Mbytes
>(or samples?) of memory.

I guess RAM that fast is not cheap.

>Joe Gwinn

[Steve Wilson]

I have 32 GB of DDR3 running at 1600MHz. Real cheap. Around CAD $196 on
Amazon.ca That's about 196/32e3 = CAD $0.006125 per megabyte, or 163.26
megabytes per dollar.

DDR4 is even faster. 3000MHz, ~CAD $248 on Amazon.

1 GB DDR3 running at 1066 MHz is around CAD $22.

These are all overkill for the application. Slower is cheaper.

1GB DDR at 400MHz is CAD $9.59 on Amazon. I can't find anything smaller.

https://www.amazon.ca/PC-3200-Desktop-Computer-Compatible-
Motherboard/dp/B07ZH5ZVC2/

Newegg is probably cheaper.

The DG4000 is 14 bits at 500MSa/s sample rate:

https://beyondmeasure.rigoltech.com/acton/attachment/1579/f-
00a0/0/-/-/-/-/file.pdf

PC ram is probably 32 or 64 bits, but I think memory addressing may return
larger chunks. So plain 400 MHz DDR ram may deliver much higher performance
than is needed for this application.





--
The best designs occur in the theta state. - sw

[Spehro Pefhany]

On Wed, 7 Apr 2021 03:14:42 -0000 (UTC), Steve Wilson <sp...@me.com>
wrote:

I assume they're using SRAM inside an moderate-sized FPGA, which may
actually be cheaper than buying a discrete SRAM 16K x 16.

I suspect DDR would add a lot of complexity for not much user benefit.

[Clifford Heath]

DDR DIMMs transfer either 64 or 128 bits in a word, with DDR4 specifying
a minimum of 8 words in a burst, or 1024 bits. Plain DDR is "only" 2 words.

CH

[Steve Wilson]

Clifford Heath <no....@please.net> wrote:

> On 7/4/21 1:14 pm, Steve Wilson wrote:

[...]

>> I have 32 GB of DDR3 running at 1600MHz. Real cheap. Around CAD $196 on
>> Amazon.ca That's about 196/32e3 = CAD $0.006125 per megabyte, or 163.26
>> megabytes per dollar.
>>
>> DDR4 is even faster. 3000MHz, ~CAD $248 on Amazon.
>>
>> 1 GB DDR3 running at 1066 MHz is around CAD $22.
>>
>> These are all overkill for the application. Slower is cheaper.
>>
>> 1GB DDR at 400MHz is CAD $9.59 on Amazon. I can't find anything
>> smaller.
>>
>> https://www.amazon.ca/PC-3200-Desktop-Computer-Compatible-
>> Motherboard/dp/B07ZH5ZVC2/
>>
>> Newegg is probably cheaper.
>>
>> The DG4000 is 14 bits at 500MSa/s sample rate:
>>
>> https://beyondmeasure.rigoltech.com/acton/attachment/1579/f-
>> 00a0/0/-/-/-/-/file.pdf
>>
>> PC ram is probably 32 or 64 bits, but I think memory addressing may
>> return larger chunks.
>
> DDR DIMMs transfer either 64 or 128 bits in a word, with DDR4 specifying
> a minimum of 8 words in a burst, or 1024 bits. Plain DDR is "only" 2
> words.

> CH

Thanks. How about DDR3? Same as DDR?

[Steve Wilson]

16e3*16 = 256,000. They are talking 8 megabytes.

FPGA SRAM has got to be expensive. Kill the RAM and use a smaller FPGA.

> I suspect DDR would add a lot of complexity for not much user benefit.

More memory gives more data points and more waveforms. They can probably
use an existing IC to manage the memory. A complete motherboard is probably
available for under $100, so the memory management portion has got to be
inexpensive.

A complete Raspberry Pi with 2 GB RAM is only CAD$47.75:

The Raspberry Pi 4 Model B is the latest product in the Raspberry Pi range,
boasting a 64-bit quad core processor running at 1.5GHz, dual-band 2.4GHz
and 5GHz wireless LAN, Bluetooth 5.0/BLE, true Gigabit Ethernet, and PoE
capability via a separate PoE HAT.

The dual-band wireless LAN comes with modular compliance certification,
allowing the board to be designed into end products with significantly
reduced wireless LAN compliance testing, improving both cost and time to
market.

Specifications:

1.5GHz 64-bit quad-core ARM Cortex-A72 CPU (Broadcom 2711)
2GB RAM (LPDDR4 SDRAM) - also available in 1GB and 4GB versions!
On-board wireless LAN - dual-band 802.11 b/g/n/ac
On-board Bluetooth 5.0 HS low-energy (BLE)
2 x USB 2.0 ports
2 x USB 3.0 ports
True Gigabit Ethernet
Extended 40-pin GPIO header
2x micro HDMI, 4k video
4 Pole stereo output and composite video port
MIPI Camera port (CSI)
MIPI Display port (DSI)
microSD format for loading OS & data storage
5V/3A DC via USB type C connector
5V DC via GPIO
PoE Enabled
Multimedia H.265 decode (4kp60), H.264 decode (1080p60), H.264 encode
(1080p30), OpenGL ES 1.1, 2.0, 3.0 graphics

https://www.buyapi.ca/product/raspberry-pi-4-model-b-2gb/?src=raspberrypi

The extra RAM could be used to add new functions as well as for more data.

They could wipe the competition for not much cost.

Dynamic RAM loses data when powered off, but a cheap flash memory could be
used to save the data and restore it at power on.

They won't be buying RAM from Amazon or Newegg, instead from their own
sources. But the Amazon prices give an indication how cheap memory has
become.

And it is fast!

[Spehro Pefhany]

On Wed, 7 Apr 2021 09:54:58 -0000 (UTC), Steve Wilson <sp...@me.com>

You would need a fast FIFO that can supply data for about 10
microseconds (IIRC) while the SDRAM refreshes, so about 80K bits. Plus
the DDR interface logic - And a Spartan 3A FPGA with 300k bits of RAM
is not expensives. Not sure if it's fast enough though, prob not.

Still if someone did an open-source RPi-based dual output function
generator using one of those cheap 240 x 320 TFT displays and a PCB
with the FPGA, DAC(s) etc on it, I bet it would be popular even if it
didn't quite measure up to the professional product in one way or
another. There is probably public domain code for the LXI
functionality. Maybe it's usable. There are DDR3 interfaces on
Opencores that claim to be finished.

https://opencores.org/projects/ddr3_sdram

That's about a $50 Spartan 6 FPGA with 1M bits of RAM, and it is fast
enough.

The gorgeous 7" color display, backlit buttons, rugged beautifully
molded case and so on definitely don't come for free.

AFAIK, I have not tested out the output protection, probably it's no
worse (or better) than the Agilent products (which use multiple
paralleled power op-amps on each output - giving off significant heat
at the best of times).

I actually built something sort of like this for a specialized task,
using a Raspberry Pi to handle the offline tasks like loading the
data. Bandwidth was << 25MHz though, so pretty lethargic.

[Lasse Langwadt Christensen]

only ~600kbit of block ram but far cheaper, https://www.ebay.com/itm/273857218909

> The gorgeous 7" color display, backlit buttons, rugged beautifully
> molded case and so on definitely don't come for free.

a 7" RPi display with capacitive touch is ~$50

[Steve Wilson]

Things have changed. RPi is now running 1.5GHz 64 bit quad core with LPDDR4
SDRAM for CAD $47.75. You can even get a compiler for Python that runs much
faster.

Cases are cheap. It's the design that is expensive. The spectacular FNIRSI-
1013D dual channel 100 MHz scope is an example. It is only US $149.68 on
eBay. The item number is 143879446906.

It has a 6" X 3 1/2" color touch display and blows most other scopes out of
the water. Unfortunately the only manual available is for the FNIRSI-5012H,
which is an older version that is not as good. I asked them yesterday for
the updated manual but have not received a reply yet. When I do, I will
post the link.

This scope is astonishing. It is a combination of all the best features of
other scopes, plus a bunch of new things. After reading the brief manual
that came with it, I was dumbfounded. Then I discovered it has an internal
battery good for 10 hours of running. No more ground loop problems! I think
everyone should get it. It is small enough to sit on the bench and not take
up much space, yet the screen is large enough to clearly display the
waveforms and measurement data.

It is so convenient to use that you will probably give up your large
mainframe scope for most low frequency work under 100 MHz. As an old user
of the TEK 7704 and 7904 scopes that needed a scope cart, this unit is
simply amazing.

With the plethora of inexpensive high quality equipment available, now is
the time to be alive if you are interested in electronics!

[Spehro Pefhany]

Nifty. Only $40 US or so.

Another product with DDR3 sockets on board.

https://www.ruten.com.tw/item/show?22048129202552

A bit over $115 USD in China + shipping.

[Spehro Pefhany]

On Wed, 7 Apr 2021 20:32:29 -0000 (UTC), Steve Wilson <sp...@me.com>
wrote:

>143879446906

There are a couple of known brand combo 3-in-1 battery powered
waveform gen + small screen 2-channel 70MHz oscilloscope + true-RMS
DMM in a bloated DMM form factor for < $200.

Might be worth throwing in the luggage if we ever get to travel again.
For fiddling around with development boards and such like it would be
enough a lot of the time. They even have replacable 18650 cells in a
holder.

[Lasse Langwadt Christensen]

you can find them on aliexpress for $25 with free shipping

[Clifford Heath]

I used Google and Wikipedia. You can too.

[Michael Kellett]

I have a DG1032Z. There is an amplitude step (on sine wave output) of
about 0.25dB at 100kHz (exactly 100kHz).
If that kind of rough edge is OK - then its good value for money.

I also have a Keysight 33600A, much nicer, no rough edges - about 10x
the price :-)

MK

[John Larkin]

On Thu, 8 Apr 2021 10:50:01 +0100, Michael Kellett <m...@mkesc.co.uk>
wrote:

I have a B+K analog function generator, which is sure easy to drive.
Just turn the knobs.

It does include a frequency counter.

[Klaus Kragelund]

Some of the generators has a glitch when you change duty cycle, in which the signal disappears when the SRAM is reloaded. I do not know if it is a problem for your device


--
Klaus Kragelund

[Joe Gwinn]

Good to know. It would not be a problem for me.

Joe Gwinn

[Joe Gwinn]

I do have a analog function generator made by B+K Precision but
without counter that I recall. Model 4040A, bought in 2003. That
generator was unusable, and so has led an isolated, dusty existence
for decades.

I always had bad experiences with B+K Precision <anything> back in the
day, and stopped buying from them. Perhaps they have since improved.

Joe Gwinn

[olaf]

Spehro Pefhany <spef...@interlogdotyou.knowwhat> wrote:


>I have the DG4062 which is similar but 500M s/s sample rate rather
>than 200.

>Nice piece of kit. Gorgeous display.

I have this thingi, too. The look&feel is a little bit strange.

But it is easy to load a waveform from your computer from
USB-Stick from CSV-File without installing fat software.

And it is also nice to made a DG4162 from it. :-)

Olaf

[John Larkin]

On Fri, 09 Apr 2021 12:09:53 -0400, Joe Gwinn <joeg...@comcast.net>
wrote:

I have a 4003A on my bench. It's been great.

[Steve Wilson]

I got the 25MHz Dual Channel DDS Function Signal Generator for US $61.63.

eBay item number: 111678169556

I don't know if it is battery powered, but any place you need a function
gen is probably line powered. $150 for the scope and $61 for the sig gen is
just over $210. I have plenty of DMMs.

The output stage on the sig gen is weak. There is a simple mod to replace
it with a better one but I lost the link.

Another sweet deal is the FA-2 1Hz-6GHz Frequency Counter, US $110.96. It
actually delivers 15 digits and is accurate to the last digit when locked
to GPS. Keysight eat your heart out. eBay item number: 113854113701. All
gone but available on Aliexpress.

Lots of other deals available. BG7TBL 1 Hz to 8 GHz sig gen, RSP1A 1kHz -
2000Mhz SDR Receiver that can also work as a spectrum analyzer, 50 KHz to 3
GHz VNA, 8 digit voltmeter, and so on. All inexpensive, should be on
everyone's workbench.

Skip all the boatanchors that take up too much space, weigh too much, and
are impossible to repair. Take advantage of modern ics and simple designs.

Now is a great time for anyone interested in electronics!

[John Doe]

John Larkin wrote:

> Joe Gwinn wrote:

>> I do have a analog function generator made by B+K Precision but without
>> counter that I recall. Model 4040A, bought in 2003. That generator
>> was unusable, and so has led an isolated, dusty existence for decades.
>>
>> I always had bad experiences with B+K Precision <anything> back in the
>> day, and stopped buying from them. Perhaps they have since improved.

> I have a 4003A on my bench. It's been great.

I have had a TOOL KIT 2703A for decades.

[Klaus Vestergaard Kragelund]

On 09/04/2021 19.23, Steve Wilson wrote:
> Spehro Pefhany <spef...@interlogDOTyou.knowwhat> wrote:
>
>> On Wed, 7 Apr 2021 20:32:29 -0000 (UTC), Steve Wilson <sp...@me.com>
>> wrote:
>>
>>> 143879446906
>>
>> There are a couple of known brand combo 3-in-1 battery powered
>> waveform gen + small screen 2-channel 70MHz oscilloscope + true-RMS
>> DMM in a bloated DMM form factor for < $200.
>>
>> Might be worth throwing in the luggage if we ever get to travel again.
>> For fiddling around with development boards and such like it would be
>> enough a lot of the time. They even have replacable 18650 cells in a
>> holder.
>
> I got the 25MHz Dual Channel DDS Function Signal Generator for US $61.63.
>
> eBay item number: 111678169556
>

I have a old 15MHz HP33120A. At one point I needed a 50MHz generator,
and bought the Feeltech FY6600:

https://www.banggood.com/FY6600-Digital-12-60MHz-Dual-Channel-DDS-Function-Arbitrary-Waveform-Signal-Generator-Frequency-Meter-p-1171428.html?cur_warehouse=CN&ID=530532&rmmds=search

It's great. Dual channel, and in some ways better than the HP

Only problem is that it is noisy, so I was testing wireless power
transfer between two coils, and measurements didn't make sense. It
turned out that the CM noise from the generator is quite high, so if you
buy it, add a lot of clamp on cores

Other tip, it is very light, and the buttons are hard to press, so place
it under some heavy gear so it stays in place :-)

[Joe Gwinn]

On Thu, 8 Apr 2021 10:50:01 +0100, Michael Kellett <m...@mkesc.co.uk>
wrote:

The Keysight 33612A (two 80 MHz channels) is equivalent to the DG1062Z
(two 60 MHz channels), but far nicer I'll grant. And it is literally
ten times the price, so I'm getting the Rigol.

I looked into Keysight's TrueForm waveform generation technology. They
mentioned that it was patented, so I went looking for the patent, if
only because the explanations in the brochures et al were baffling.
The explanation is in the "Arbitrary Waveform - A high performance AWG
primer - Fundamentals of Generation" Reference Guide, 2015, Manual
Part Number M8190-91050, Edition 4.0, June 2015, Keysight Germany.

This document cites "US Patent 6,812,878 B1, Jewett et al. Per-Element
Resampling for a Digital- to-Analog Converter", which will expire in
April 2023. To get a copy, go to Google advanced patent search, enter
US6812878 in the big box, then download the pdf.

It won't be long before there is a Chinese clone of the 33612A.
Probably already done, but not sold in the US until that patent
expires.

Joe Gwinn

[Steve Wilson]

Klaus Vestergaard Kragelund <klau...@hotmail.com> wrote:

[...]

> I have a old 15MHz HP33120A. At one point I needed a 50MHz generator,
> and bought the Feeltech FY6600:
>
> https://www.banggood.com/FY6600-Digital-12-60MHz-Dual-Channel-DDS-Functio
> n-Arbitrary-Waveform-Signal-Generator-Frequency-Meter-p-1171428.html?cur_
> warehouse=CN&ID=530532&rmmds=search
>
> It's great. Dual channel, and in some ways better than the HP
>
> Only problem is that it is noisy, so I was testing wireless power
> transfer between two coils, and measurements didn't make sense. It
> turned out that the CM noise from the generator is quite high, so if you
> buy it, add a lot of clamp on cores
>
> Other tip, it is very light, and the buttons are hard to press, so place
> it under some heavy gear so it stays in place :-)

Wow! 30 MHz is CA$125.30. Double the frequency to 60 MHz and the price only
increases to CA$135.57. That is a bargain.

The manual is at http://gotronik.pl/img/FY6600_Series_Users_Manual.pdf

I want one!

Now is a great time to be alive for electronishers.

The price trend seems to be across the board. I used to play in a dance
band on the weekends while I was stationed in Europe with the RCAF. We
weren't very good, but it didn't matter. Everyone was blitzed by the time
we arrived and they would dance to anything.

In those days, a Fender Stratocaster would have cost a fortune if it were
available. But over the years the price has dropped, and now it is a very
affordable CAD $299.99 on Amazon:

https://www.amazon.ca/Fender-Stratocaster-Beginner-Fingerboard-
Sunburst/dp/B07G4VRMWZ/

It is a real strat. Made in Indonesia but excellent quality. Very good
therapy after spending a day flogging electrons.

There is a streaming site that plays 1930's jazz that is nice to play along
with:

http://195.176.247.102:8000/classical.mp3

[John Miles, KE5FX]

On Friday, April 9, 2021 at 3:34:53 PM UTC-7, Joe Gwinn wrote:
> It won't be long before there is a Chinese clone of the 33612A.
> Probably already done, but not sold in the US until that patent
> expires.

I skimmed the patent, but I don't understand what problem it solves. How
do those timing glitches make it through the reconstruction filter? Seems like
they would settle almost instantly (and the background section says as
much, near line 30 on page 6.)

It's definitely not the sort of patent that would block competitors at
this point in time. There are a lot of patents like this, written to work around
shortcomings in ADCs and DACs of 20 years ago that no longer exist in
modern ICs.

-- john, KE5FX

[Joe Gwinn]

On Fri, 9 Apr 2021 16:49:03 -0700 (PDT), "John Miles, KE5FX"
<jmi...@gmail.com> wrote:

>On Friday, April 9, 2021 at 3:34:53 PM UTC-7, Joe Gwinn wrote:
>> It won't be long before there is a Chinese clone of the 33612A.
>> Probably already done, but not sold in the US until that patent
>> expires.
>
>I skimmed the patent, but I don't understand what problem it solves. How
>do those timing glitches make it through the reconstruction filter? Seems like
>they would settle almost instantly (and the background section says as
>much, near line 30 on page 6.)

The secret source is in the Encoder block (number 102), which is
completely unconstrained in US 6,812,878. The reference guide gives
some idea of what's being done.

Often the various details are scattered about in multiple patents,
which are usually most easily found by searching what else the named
inventors have done. Jewett seems to be the main name, and may have
published an article in the International Solid-State Circuits
Conference.

And in any case, the above may be our best source to understand the
principles of operation.

>It's definitely not the sort of patent that would block competitors at
>this point in time. There are a lot of patents like this, written to work around
>shortcomings in ADCs and DACs of 20 years ago that no longer exist in
>modern ICs.

Yes, but the point here is to get around the limitations of cheap
DACs, on the trailing edge of technology, not the current leading
edge. Texas Instruments has some amazing DACs and ADCs, which cost
thousands of dollars per chip.

Joe Gwinn

[Spehro Pefhany]

On Fri, 9 Apr 2021 18:10:24 +0200, olaf <ol...@criseis.ruhr.de> wrote:

>
>And it is also nice to made a DG4162 from it. :-)
>
>Olaf

Interesting hack that one.

[John Larkin]

On Sat, 10 Apr 2021 19:34:47 -0400, Spehro Pefhany
<spef...@interlogDOTyou.knowwhat> wrote:

>On Fri, 9 Apr 2021 18:10:24 +0200, olaf <ol...@criseis.ruhr.de> wrote:
>
>>
>>And it is also nice to made a DG4162 from it. :-)
>>
>>Olaf
>
>Interesting hack that one.

All our 350 MHz Rigol scopes are actually 500 MHz. We just asked.

[Spehro Pefhany]

On Fri, 09 Apr 2021 12:09:53 -0400, Joe Gwinn <joeg...@comcast.net>
wrote:

>

>I always had bad experiences with B+K Precision <anything> back in the
>day, and stopped buying from them. Perhaps they have since improved.
>
>Joe Gwinn

I have a BK triple power supply on a tertiary bench- it's just a
rebadged supply made by one of the major Chinese (Shenzhen) power
supply firms, also sold under their own name, Velleman etc.

More of a consumer product construction than an instrument, but solid
enough.

[Joe Gwinn]

Yes, there's that.


But my answer to American firms selling the lower end of Chinese stuff
is: If I'm getting Chinese quality, I want Chinese price too.

So, I do buy Harbor Freight stuff, but with low expectations.

I've had better luck buying Chinese brands that are selling in their
own name, who are clearly are trying to be world class. Rigol being
one example.

Joe Gwinn

[John Doe]

Hopefully everybody in your country will treat you
the same way you treat them...

--
Joe Gwinn <joeg...@comcast.net> wrote:

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> From: Joe Gwinn <joeg...@comcast.net>
> Newsgroups: sci.electronics.design
> Subject: Re: Rigol Function Generators - experience?
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[Clifford Heath]

On 12/4/21 5:21 am, Joe Gwinn wrote:
> On Sat, 10 Apr 2021 19:46:09 -0400, Spehro Pefhany
> <spef...@interlogDOTyou.knowwhat> wrote:
>> On Fri, 09 Apr 2021 12:09:53 -0400, Joe Gwinn <joeg...@comcast.net>
>> wrote:
>>> I always had bad experiences with B+K Precision <anything> back in the
>>> day, and stopped buying from them. Perhaps they have since improved.
>>> Joe Gwinn
>> I have a BK triple power supply on a tertiary bench- it's just a
>> rebadged supply made by one of the major Chinese (Shenzhen) power
>> supply firms, also sold under their own name, Velleman etc.
>>
>> More of a consumer product construction than an instrument, but solid
>> enough.
>
> Yes, there's that.
>
> But my answer to American firms selling the lower end of Chinese stuff
> is: If I'm getting Chinese quality, I want Chinese price too.
>
> So, I do buy Harbor Freight stuff, but with low expectations.

Quality is only a small part of the price equation. Chinese sellers do
not have to provide any statutory (mandatory) warranties, are not tested
to any performance standards, and cannot easily be sued if the device
fails to meet specifications, or even if it blows up and kills someone.

Most "American" products are just Chinese-made devices with proper
testing, warranty and liability protection. Adding those things (without
any change in the design or manufacture) approximately triples the cost
of doing business.

Harbour Fright provides just the minimum of these protections, which is
why you pay a little less.

CH

[Joe Gwinn]

Huh? How is triple "a little less"?

More to the point, quality has nothing whatsoever to do with "proper
testing, warranty and liability protection" - all these do is to
ensure that some government mandated requirements are met, which may
or may not be a good idea, but is unrelated to how well a product
works for its intended purpose, and how long it continues to do so.

One cannot test quality into something, quality must have been
designed and built into the product from the beginning.

Nor should "proper testing, warranty and liability protection" triple
the cost.

Joe Gwinn

[Johnny B Good]

That's a three year old model! Feeltech / FeelElec have since done an
FY6800 and, currently an FY6900 model which looks a better bet. The
latest 6900 model revision now uses a single 5v rail smpsu board with the
+/- 13.7v rails generated on the main board making the option to replace
the source of the high levels of CM switching noise with a small analogue
PSU board a whole lot easier.

Unless you want to upgrade its cheap 10MHz smd XO chip to an OCXO, you
only need 5v at 2A to power the main board.

A comprehensive source of info on these dirt cheap AWGs can be found in
the EEVBlog forum.

<https://www.eevblog.com/forum/testgear/feeltech-fy6600-60mhz-2-ch-vco-
function-arbitrary-waveform-signal-generator/msg1266953/#msg1266953>

I didn't join this FY6600 topic thread until reply #1702 (page 69)

<https://www.eevblog.com/forum/testgear/re-feelelec-new-arrival-fy-6900-
signal-generator/msg2564763/#msg2564763>

I started contributing to this FY6900 topic with reply #33 (page 2)

Anyone interested enough to view these topics (you can read any EEVBlog
topic as a guest - no need to sign up for membership unless you want to
post) will see that the FY6600 was mentioned in this very news group way
back in October 2018!

You'll also see the story about how reading the "amazing ARB pricing"
thread in the SED NG had led me to my very first DSO purchase, swiftly
followed by the infamous FY6600-60M a week later after comparing it
against the cheapest of Siglent's 2CH AWG models the SDG1032 which then
weighed in at an extra 280 quid.

The choice, for a first time punt on a signal generator was a no-brainer
and, despite some obvious but fixable shortcomings, proved in the event
to be one of the wisest choices I ever made. You can see why I'd come to
that conclusion by reading my contributions here:-

<https://www.eevblog.com/forum/testgear/the-siglent-sdg2042x-thread/
msg3546785/#msg3546785>

BTW, you're not wrong about how lightweight it is! :) However, I'm using
my shiny new SDG2042X simply as a plinth to raise my much modded FY6600-M
to a more convenient level above the bench top.

Until Siglent finally fix its UI issues to fully realise its potential,
that expensive SDG2042 simply isn't up to the task of syntonizing a
Rubidium reference to a GPSDO reference in 10μHz (or even 1μHz)
increments as I am able to do by feeding it into the external reference
socket on the back of the FY6600 so as to dial in calibrated frequency
offsets without putting needless wear and tear on the LPRO-101's trimpot
whilst I work on my project to create a temperature stabilised RFS for my
workshop.

In essence, to quote from the SGD2042X thread,

"For now, I'm experiencing the rather unexpected situation where the
expensive AWG is reserved for the "Less Demanding" work whilst that cheap
'toy' FY6600 is my go to AWG for the more demanding tasks."


--
Johnny B Good