Looking for ROM images for HP 53181A counter - Page 1
Forum section: electronics / repair

author: TERRA Operative
author_rank: Super Contributor
timestamp: January 18, 2024, 12:03:09 am
content: I'm currently repairing a HP 53181A counter and am looking for later version ROM'sI have version 3073 but I know that at least version 4243 was available.If anyone has one of these counters and a chip programmer, and has a later firmware than 3073, I'd greatly appreciate a dump of your chips.They are socketed so it's easy to do and it won't affect calibration etc.Thanks!

author: C-47
author_rank: Regular Contributor
timestamp: January 18, 2024, 02:37:26 am
content: I have version 3418 but how to download it is the question, hopefully someone will appear with a later version. Alan.

author: TERRA Operative
author_rank: Super Contributor
timestamp: January 18, 2024, 04:49:11 am
content: When I upgraded the firmware in my 53132A I just used my TL866II programmer with an adapter, but one would need a programmer.

author: picburner
author_rank: Frequent Contributor
timestamp: January 18, 2024, 07:41:53 am
content: Not found v4243 but v3944 only

author: TERRA Operative
author_rank: Super Contributor
timestamp: January 20, 2024, 05:33:04 am
content: Great, thanks. That's at least a step up from mine.If anyone has a later revision, gimme!

author: gamalot
author_rank: Super Contributor
timestamp: January 20, 2024, 02:13:10 pm
content: The firmware version of my 53181A is 4243.

author: TERRA Operative
author_rank: Super Contributor
timestamp: January 20, 2024, 02:54:40 pm
content: Fantastic! Thank you so much for the ROM's!

author: jonese
author_rank: Contributor
timestamp: January 20, 2024, 10:34:34 pm
content: My 53181A came with firmware3418. Is it okay to jump directly to4243? Do I need to concern myself with dumping the calibration data before hand at all? Not that I could right now anyway, as I don't have a HP-IB interface.

author: TERRA Operative
author_rank: Super Contributor
timestamp: January 21, 2024, 05:58:02 am
content: You will need to recalibrate, but it doesn't need GPIB to do so. It can all be done from the front panel and is pretty easy to do.You'll need a 10MHz reference, a DC PSU good for exactly 5.000V, a decent DMM (good to microvolt accuracy is needed apparently, but a 4.5digit DMM or greater is probably fine), and various interconnect adapters.https://www.keysight.com/us/en/assets/9018-01065/service-manuals/9018-01065.pdfPage 1-4 for equipment required (Ignore the Pulse gen and Time Interval Calibrator requirement for the 53181A).Page 2-25 for the actual cal procedure.

author: jonese
author_rank: Contributor
timestamp: January 21, 2024, 04:02:30 pm
content: It's an easy calibration for the 181, Thank you

author: hp3310a
author_rank: Regular Contributor
timestamp: April 08, 2025, 05:36:13 pm
content: New proud 53181a owner here, so naturally I'm interested. How do you get the version number? Is it the revision number shown in the utility menu? What except for the TL866II programmer would one need to update it?

author: bingo600
author_rank: Super Contributor
timestamp: April 08, 2025, 05:47:17 pm
content: Quote from: TERRA Operative on January 18, 2024, 04:49:11 amDid you "Home calibrate" the 53132 ?If yes -Any tips for equipment & steps ?

author: TERRA Operative
author_rank: Super Contributor
timestamp: April 08, 2025, 11:53:48 pm
content: Quote from: hp3310a on April 08, 2025, 05:36:13 pmHold the  button in while you switch on the instrument and the firmware revision will be displayed.If the ROM chips are EEPROM (mostly found in later instruments), then you can just pop them out of the IC sockets, flash them with the new firmware, stick them back in then run a full calibration.If they are One Time Programmable PROM chips, then you'll need to get replacement chips to program the new firmware into.You want four of 128k x 8 parallel PROM/EEPROM/Flash/etc in a PLCC-32 package, something like this or an equivalent, whatever you can get your hands on should work:https://www.mouser.com/c/semiconductors/memory-ics/eprom/?organization=128%20k%20x%208&package%20%2F%20case=PLCC-32&instock=yQuote from: bingo600 on April 08, 2025, 05:47:17 pmThe calibration process can be found in the manuals available around the internet It's pretty basic. You basically need a 10MHz reference (I used a GPS reference), a precise +5V monitored by a 4-or-more-digit multimeter to ensure it is accurate (I used a DC power supply and bench multimeter), and if you want to run the 'Fine' Time Interval calibration and you don't have the required pulse generator and calibration fixture, you can substitute with a good waveform generator that can output both a 10MHz square wave and an inverted 10MHz square wave simultaneously at 1V peak-to-peak.The 4-step sequence is as follows (You can use BNC Y-adapters and equal length BNC cables).Input: Channel 1 - Channel 21: Standard Waveform - Standard Waveform2: Standard Waveform - Standard Waveform <- Swap both BNC inputs at frequency counter3: Standard Waveform - Inverted Waveform4: Standard Waveform - Inverted Waveform <- Swap both BNC inputs at frequency counterIf you have an OCXO option installed, I suggest tweaking the OCXO manual adjustment pot to get it as close to 10MHz before running the OCXO auto tune routine. The instrument only has a small amount of auto adjustment range, so it can fail if the OCXO is too far out of adjustment.Here's how you do it:1 - Let the instrument warm up for a few days (The OCXO is always powered when the instrument is plugged in to mains power, even when switched off, so you don't need to have it actually on and running the whole time it's warming up and settling).2 - Take the outer cover off your frequency counter to access the OCXO.3 - Connect a reference 10MHz frequency (I use a GPS reference) to Channel 1 your oscilloscope and trigger from it.4 - Connect the 10MHz reference out from the frequency counter to Channel 2 on your scope.5 - Tweak the adjustment on the OCXO until the moving Channel 2 trace is as stationary as possible. Let it settle for a bit and retweak as many times as you want until you get bored.6 - Reinstall the case, let it settle again and recheck with the scope and retweak as needed.7 - Run the OCXO auto calibration routine.The frequency difference between the reference frequency and instrument output frequency can be calculated as follows:Frequency difference = 1 / (Time taken for instrument waveform to scroll by one full period duration relative to the reference waveform, in seconds)If the frequency counter waveform is scrolling towards the left relative to the reference waveform, then its frequency is higher. If the waveform is scrolling towards the right, then its frequency is lower.

author: hp3310a
author_rank: Regular Contributor
timestamp: April 10, 2025, 08:51:48 am
content: Quote from: TERRA Operative on April 08, 2025, 11:53:48 pmThanks for the detailed instructions!