Re: 8920B Receiver Synth "Out of Lock"
OK. Took me a while but finally have the correct # for my Rx Synth: 08921-61020
Will call Ric on Monday.
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I am sorry if I misunderstood. Are you interested?
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Wally
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On Friday, November 22, 2024, 12:05:39 PM UTC, Wallace Gasiewicz via groups.io <wallydoc@...> wrote:
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I still have the units.
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On Friday, November 22, 2024, 4:00:04 AM UTC, Hank Riley via groups.io <n1ltv@...> wrote:
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What happened Wally?
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HR
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Re: 8920B Receiver Synth "Out of Lock"
Cool! I looked at Amtronix and did not see 08920-61020 but did see some others. Not sure of any compatibility issues.
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Re: 8920B Receiver Synth "Out of Lock"
Well so much for that! I pulled the board and it doesn't match the CLIP. There's a single PLCC in place of the two dividers. :-(
Should have known as I have 08920-61020 and the CLIP has 08920-68127.
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Cannot find extenders anywhere and no schematic so may have to gamble with ebay. I hate that!
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Mark
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Re: 8920B Receiver Synth "Out of Lock"
Hi Mark,
?? Your problem could be the reference or the receiver synthesizer. We have the receiver synthesizers for $100. Call rick at amtronix to get one.
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8920B Receiver Synth "Out of Lock"
Hi group!
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New member here. I have an 8920B here that I repaired some time ago (power supply failure) and considered it working.
But the other day used it to test a transmitter and no Tx frequency! Found the Receiver Synth has no PLL lock. (hopefully that's the only issue)
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I have repaired a few ESA Series SAs with this error and in all cases, it was a failed divider. I see from the 8920 schematic that it uses a similar scheme as the ESA series. (VCO to dividers to Frac-N divider)
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Looks like a bear to troubleshoot w/o extender cards. Has anyone seen this before? (divider failure)
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Thanks!
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Mark
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On Friday, November 22, 2024, 4:00:04 AM UTC, Hank Riley via groups.io <n1ltv@...> wrote:
What happened Wally?
HR ________________________________________________________
On Friday, October 25, 2024 at 01:45:58 PM EDT, Wally wrote:
Since the Ft Wayne Indiana Hamfest is coming up, Nov 16.... I have two units that I am taking offers on.
If you would like to pick up one of these units at Ft Wayne, make an offer.
I am in Indianapolis.
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What happened Wally?
HR ________________________________________________________
On Friday, October 25, 2024 at 01:45:58 PM EDT, Wally wrote:
Since the Ft Wayne Indiana Hamfest is coming up, Nov 16.... I have two units that I am taking offers on.
If you would like to pick up one of these units at Ft Wayne, make an offer.
I am in Indianapolis.
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Since the Ft Wayne Indiana Hamfest is coming up, Nov 16.... I have two units that I am taking offers on.
Both? have been tested on my bench and I have not found any problems at all.
The 8935 has a beat up case but the front panel is in excellent shape. It has a front panel cover.
The 8922 has only a 25 Watt input and does have the spectrum analyzer.
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All connectors on both units are in good shape.
If you would like to pick up one of these units at Ft Wayne, Make an offer.
I am in Indianapolis.
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Wally KC9INK
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Hi All,
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I have what I think is a fairly late model h/w & s/w unit, see screen shot.
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Would love to share latest firmware, but getting it out of onboard flash into PCMCIA card might be tricky if at all. Looking for guidance?
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The unit had 3 dead batteries, 2 on PCB and the pair of AA at the rear with free leaked battery alkaline substance.?
The unit is very healthy and close enough to calibration even though all backup batteries were flat¡..
This has been asked, has anyone obtained the calibration s/w card?
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Regards
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Gerald
VK3GM
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Re: Features and options in an HP 8920A
If you have strong signals from the local TV stations, The ATSC pilot carrier is usually network tied to GPS and I see them within a couple of hertz of each other here.? Have to have a pretty strong signal to calibrate from the input though.? Look it up and you will see the standard is much less than 1 Hz (although some may be required to offset to avoid interference).
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You have to almost find the old HP computer that can run and debug the HP BASIC, but the instrument can debug whatever you upload to the instrument as text.? Kind of like throwing it against a window to see if it sticks.
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The instrument has 2 rs-232 ports and can be used to feed instructions into the instrument, then run the program and catch output to the printer or a text file.? I did run the setup dump program found in the files section and it ran perfectly (but slow).
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The next nightmare you will run into, is A model saves setup screens in LIF internally but somehow saves to DOS in the card if it is fornatted that way.? I was hoping to back them up to a hard drive and fill the card and/or machine so I don't lose them in the card to a dead battery.? The programming manual is kind of a tease and I don't have time to reverse engineer the whole syntax and command structure.? The answer may be to hack up an Epson card R/W for the computer, or run a program in the machine to file manage with a terminal program in the computer.
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Re: Features and options in an HP 8920A
All good Dave.
Bill M.? ?VK6IC
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Jim: Thanks for the info and advice.
[snip for brevity]
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Bill/VK6IC: ?Thanks again for your comments.
[snip for brevity]
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On Tuesday, my GPSDO should arrive. ?I'll re-seat the boards and run the frequency test and let you know what I get.
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David, AK2L
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Re: Features and options in an HP 8920A
John,
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I'm using an old Windows XP laptop. I made a custom RS-232 serial cable to communicate between the HP8920A and the laptop.?I have an old Thinkjet printer connected with HPIB. I don't think the HP Basic software runs on newer versions of Windows. Here is a link to Amtronix website for downloading the HP BTS screen capture utility.
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73,
AE8J
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On Monday, September 16, 2024 at 12:59:35 PM EDT, j.kernkamp@... wrote:
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Andy -
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The hard part is creating a program and somehow getting it into the analyzer.
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I just uploaded a file - App Note 8920-1.pdf - that goes a long way toward explaining this process.
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It would be good to get this into a more simplified explanation, with more clearly explained steps, but I don't have the time at the moment.
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If someone gets it working well, perhaps they can write up their procedure details for the rest of us.
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John K.
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Re: Features and options in an HP 8920A
Jim: Thanks for the info and advice.
When G8PRI mentioned Amtronix, I knew something was familiar about that name, but couldn't put my finger on it. ?Then when I looked at Amtronix's web site I remembered that I had purchased a nice return loss bridge from them at Hamvention 2014.
I have lots of screen photos, some of them with captions. ?So that should prove to a prospective customer that the unit is indeed working.
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Bill/VK6IC: ?Thanks again for your comments.
The unit had been on for a while when I first ran the RF Diags suite. ?It reported 3 errors, not 2. ?I let the unit run overnight and ran the suite a couple times more. ?The third error never reappeared.
I like your idea of re-seating the PCBs. ?(Reminds me of a Macintosh I had years ago. ?About every 6 months I had to reseat the memory modules or the computer would randomly crash due to memory errors!)
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On Tuesday, my GPSDO should arrive. ?I'll re-seat the boards and run the frequency test and let you know what I get.
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David, AK2L
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Re: Features and options in an HP 8920A
Andy -
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The hard part is creating a program and somehow getting it into the analyzer.
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I just uploaded a file - App Note 8920-1.pdf - that goes a long way toward explaining this process.
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It would be good to get this into a more simplified explanation, with more clearly explained steps, but I don't have the time at the moment.
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If someone gets it working well, perhaps they can write up their procedure details for the rest of us.
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John K.
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Re: Features and options in an HP 8920A
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Hi Bill,
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Here are three links to HP manuals pertaining to IBASIC that will get you started.
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73,
AE8J
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Re: Features and options in an HP 8920A
Hi David,
Some comment on doing the tests. Offered in good faith.
Be sure to allow perhaps 1 hour with the unit on, to get a stable Internal oscillator before performing the test routines.
Use a good quality Coax Cable for the rf tests. I think my unit asks me to connect RF IN/OUT to Duplex in, and does a quick test to determine the attenuation of the test cable, this is then applied to the test regime to avoid cable losses. An intermittent cable will be? great problem.
It is interesting that the figures on your results have low values. I will check my notes from my travels through the beast last year. I seem to remember that I have seen this fault before. I did clean the edge connectors with a proprietary electronic cleaner, and make sure the PCBs are seated well. The 255 value seems OK , I am not sure if that is fully attenuated or a through connection ( No Attenuation)
It may be that the DAC concerned actually has a faulty component. Perhaps try to output some RF of a certain value and measure with another level instrument. I.E. your ham receiver "S" meter, after doing a clean and inspection. I take notes when working on My HP, noting what I did and when, plus the Results / Changes . Thus I can look back at the notes and check if I had this problem in my unit, and what I did to fix it.
I bought a GPSDO on ebay, it works very well.
Regards
Bill M? VK6IC
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Re: Features and options in an HP 8920A
Hi Andy, I am interested in your comment about using the compiler in the HP8920A.
Tell me more ... What do I need to get into this? Can I interface my Windows 7 or 10 to talk to the HP ? I do have RS232 I/F option on my 8920A, and an OKI RS-232 Printer.
Any links to software programs I would need?
Regards
Bill M.? VK6IC
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Re: Features and options in an HP 8920A
I have one with 001,002,003,004,005 and I researched greatly to find one with these options.? It has everything you need for Ham use and is even more than I need for the 2-way customers I service.? Most have the standard 60 watt input limit.? There were also options for much lower maximum input.? It is good to use an external attenuator anyway so you don't burn your baby.?
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This was an upgrade from my IFR and the monitors at work.? I am semi retired and only do Analog systems, but I used to calibrate the modulation in digital stations as well.? It has no usable trunking features for the latest encrypted trunking systems but I sought this one for its ability to operate down to 400 kHz and HF SSB service as well as FM systems.? And the kicker is the 002 Tracking option for aligning duplexers and the High stability oscillator 001 is what I was also looking for to take care of 800 MHz systems.? It is also able to be checked out and calibrated without expensive and proprietary codes and keys.? There is ample information in the files section of this group and on the internet, even to do repairs if you dare.?
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All the advice given so far is good and Amtronics is a good place to start with looking up the features and some tips for operation.?? Mine has ver A14 firmware and it might be useless to update yours unless the hardware can support it and make use of it.? If I remember correctly, firmware was for production changes and some programming syntax,? and options that became standard and some of the option numbers changed because of this. There are 2 different documents out there for the A models that list different option numbers and modules.? The giveaway is the option 002 Spectrum analyzer, mine has tracking but no ACP? but it may have been added later.? Later models had an option 102 spectrum analyzer with tracking and ACP but I don't know if your firmware supports it.? The rest you have right.? In any case you could take the cover off and see the part numbers on the modules to see what is really there. ? The later model A and B, went to a solid state switched attenuator that didn't perform well on lower frequencies and had reliability problems, and a new board to support PCMCIA memory cards.? Note that for some module replacements, you will require the factory PCMCIA or Sram card with calibration data for that module.
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The internal memory is for operation of the unit and to save custom setups and programs so you can recall them from a list you have saved.? Cats meow!? There are external memory cards sort of available, that are the same as Epson 40 pin Sram cards that were used for voting machines, calculators and printers.? They are in the $100 plus range and you will spend many hours or days to find them at that reasonable cost.? The down side is that you have to change the battery every 6 months while the card is plugged into the unit, or the memory in the card is lost.
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This family of service monitors has the capability of being married to various hardware in a production or automated shop, and can be programmed in HPBASIC for a complete testing routine that can produce a report on the unit under test.? These tests can be from the card, the instrument's memory or remotely via GPIB link.?
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Mine was about $2000 on ebay 5 years ago.? When you advertise it take good photos and show the display with the options and self-test passed.? Most buyers will assume that if it isn't powered up, it doesn't work or the screen is dying.? These were often lovingly guarded in the lab while the grunts in the field lugged around older heavier monsters that got beat up.? Someone said that it is heavy, but is the lightest I have used except for an FM/AM 1000S I used in the 70s.? People still search for the FM/AM 500 even though it rediculously bare bones, because it is small and light and makes a good movie prop.? There are a whole bunch of used monitors out there that are lighter and cheaper, but have features that are for obsolete or specific tasks and are useless to many.? I was dismayed to find that many don't even have a high stability timebase.?
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Jim
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Re: Features and options in an HP 8920A
* Andy: I confirmed that:
- the RF Generator produces a nice sine wave down to (at least) 100 kHz
- the Spectrum Analyzer correctly displays an externally-generated, modulated AM signal at 400 kHz
- the RF Analyzer correctly interprets an externally-generated, modulated AM signal at 400 kHz
So yes, it would seem to have the mechanical attenuator.
Thanks for the tips on additional diagnostic tools.
* Bill/VK6IC: Thanks for the info about the built-in tests. ?I ran all three suites.
- RF Diags
This did not ask me to make any connections. ?Perhaps it is because the unit has an earlier firmware version?
In any case, 2 tests failed in the "Output Variable Attenuator", "Suspect: Input Assembly (High)". ?See photo.
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All other tests in this suite passed.
- AF Diags
This suite did ask me to make connections, which I did. ?All tests passed.
- MS Diags
This suite has 3 tests. ?Two passed. ?The third requires an external 10 MHz reference. ?I don't own one so I just ordered one.
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* Robert/G8RPI: ?Thanks for the info about Amtronix.
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David, AK2L
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