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Folks
I believe that there is a lot of similarity between these test sets, I have had an MT8802A for about four years now with the spectrum analyser (option 07).
Over the past three years, although the analogue receiver tester has been working perfectly, the analogue transmitter tester and spectrum analyser have been misbehaving intermittently to the extent where I'd stopped using them. Most notably the tx tester worked increasingly intermittently or was terribly deaf, and the spectrum analyser was unstable or otherwise significantly off frequency, and it did not measure levels accurately.
Although the symptoms weren't specifically mentioned here http://www.kolumbus.fi/oh5iy/HW/MT8802A.html I decided to bite the bullet and do an electrolytic transplant over the past day and a half.
The results have been superb, all of those intermittent problems appear to have gone.
I wouldn't recommend doing it unless you have a lot of patience and you can accept having the unit out of action for a couple of days. There are tons of screws to keep track of, and about twenty boards to get through. The power supply and A10 converter seemed to fix most of my problems, and I did those first anyway, but I thought as I'd already started I might as well do the lot.
Removing some of the caps wasn't always easy. I used a Weller DSX80 on a WMD-3: they've been in a box for about four or five years as I only really do SMD on boards these days for projects, it's very rare that I need a through hole on a board. While it worked, much of the time I found that touching up the exposed cap pin stubs on the underside of the board with a bit of full fat solder helped with the heat transfer and suction on the (mostly) multilayer boards.
If you have one of these test sets and are experiencing odd problems, I can recommend the cap replacement procedure, but unfortunately there aren't many short cuts to replacing electrolytic caps. -
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ough the symptoms weren't specifically mentioned here http://www.kolumbus.fi/oh5iy/HW/MT8802A.html, I decided to bite the bullet and do an electrolytic transplant over the past day and a half.
Hi Howard
Your link doesn't work because there is a comma at the end
Hope the one below works OK ...
http://www.kolumbus.fi/oh5iy/HW/MT8802A.html
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Intermittant problems are often poor contacts. Taking everything apart probably solved the problem.
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Maybe... but the insides of something like this can run quite hot and this can shorten the capacitor life and cause multiple failures after many years' service.
I've had to replace a few dead caps in my old HP8566B analyser and they caused similar symptoms. In my case I used a simple homemade in circuit ESR tester (function gen + sense resistor + 100kHz receiver) and tested all the caps in the suspect areas.
I found several dead caps that had gone high ESR.
I'm not a fan of blindly recapping complete units mainly because of the time and cost and also the risk of causing damage or fitting inferior performing parts. To replace that many caps that is shown by Howard (with new high grade ones) would have cost me more than I paid for my complete HP8568B analyser about 7-10 years ago (£125). I tend to wait for an obvious failure or issue and then try and find the cause. I'm too much of a tightwad I guess
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I did also clean up a couple of dozen trimmer pots which could also have had an effect.
Some of those caps had ESRs in excess of 20 ohms, most were between 7 and 10 ohms. They were all past their prime that's for sure.
Had I had a service manual for it, I would have done a rather more analytic approach, but I've been unable to locate one.
In fact, documentation for the analogue rx/tx and spectrum analyser parts online seems lacking. There is documentation available for the GSM/CDMA etc functions for what that is worth. The UI isn't the best I've had the pleasure of using, but I've used worse.
The MT8802A is pretty useful, as as well as a 3GHz spectrum analyser, it has a 3GHz RF signal generator and power and modulation measurement, again to 3GHz, although the modulation capablities are limited to FM, and there is no tracking generator. But light it ain't. -
I keep an MT8801B on my bench as a general purpose tool. Lovely bit of kit though the display is a week design and it's useful to know that they suffer from poor caps.
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I keep an MT8801B on my bench as a general purpose tool. Lovely bit of kit though the display is a week design and it's useful to know that they suffer from poor caps.
Do you by any chance know what the differences are between the '01A/B/C and '02A? -
Some of those caps had ESRs in excess of 20 ohms, most were between 7 and 10 ohms. They were all past their prime that's for sure.
From your photo, I can't tell the date code on any of the capacitors? Can you tell us what age they are? -
Not sure about cap date codes, but the latest chip code I've found on one of the documentation photos I took was 9937.
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I keep an MT8801B on my bench as a general purpose tool. Lovely bit of kit though the display is a week design and it's useful to know that they suffer from poor caps.
I've been using it with some venom this morning for the first time since doing a cap repalcement. i wasn't sure when I was doing the cap replacement, but I felt that the display was markedly clearer, right after the cap replacement on the main PSU, which happened to be the first board I did.
Note: Good bit of advice, test the unit after each board's been recapped, or else it could end in tears: the last boards I did were the two SG boards, and I'd forgotten to re-solder the dozen or so feed-throughs underneath a screening plate. Had I just recapped all twenty or so boards and switched it on, I could have had a fun time tracking that down. I recommend doing both an analogue RX and TX test plus a spectrum analyser test after each board if that option's installed for a minimally comprehensive test.
Now I've used it for a few hours, I am absolutely certain that the screen is significantly clearer. Note that I didn't recap anything on the screen itself, or its backlight inverter. Originally the screen seemed a bit washed out without much contrast, now it seems pretty reasonable. -
I keep an MT8801B on my bench as a general purpose tool. Lovely bit of kit though the display is a week design and it's useful to know that they suffer from poor caps.
Do you by any chance know what the differences are between the '01A/B/C and '02A?
I've not noted any significant differences, however I've not played much with the 02A or the 01A -
I guess what I'm alluding to is do they have the following functionality...
A) Analogue receiver tester, to 3GHz
B) Analogue transmitter tester, to 3GHz
C) Full span spectrum analyser, to 3GHz
The cellular stuff for me is just an irritation to bypass when you first switch on, or is there a way to go straight to, say, the analogue receiver tester? I'm not really interested in a floppy-based setup solution, by the time you've done that you could have already manually pushed the buttons yourself! The settings themselves for the spec an and analogue tests are maintained through power down.
The other irritation is the boot time, about five minutes or so. When I first switched on my MT8802A, I thought it had crashed, as much of the boot time is with a blank screen after the first CPU and memory self tests.
But it is a good all round unit. If I could find some documentation for the analogue and spectrum analyser sections that would be a bonus.
By the way, after re-capping the CPU board I had to do a full reset by holding the Preset button while turning it on, a bit frustrating as I had to spend a while trying to remember how I'd configured the rx tester SINAD settings correctly. -
I guess what I'm alluding to is do they have the following functionality...
A) Analogue receiver tester, to 3GHz
B) Analogue transmitter tester, to 3GHz
C) Full span spectrum analyser, to 3GHz
From memory, The 8801A/B/C, then A) and B) is only if option 01, analog tester is installed.
For the spectrum analyzer, this is option 07. The all have the same basic functionality with those options installed.
With both those options, then you have a box with spectrum analyzer, signal generator, frequency counter, modulation meter all up to 3GHz, as well as some simple audio input and output functions.
Without those, then it's just a way of testing whatever mobile phone that the system has been installed. I've not noticed a long boot time, however I've just done a fresh power up on a MT8801B and an MT8801C and the B booted quickly and the C took a few minutes, most of which was with a blank screen. It seems like Anritsu has taken some lessons from Microsoft.
Quick advert time, but both are available for sale, the B has options 01 and 07 installed, the C is just for GSM measurements. PM me for details. -
Hi Howard,
I finally registered at this forum as well. I am in the process of recapping.
Did you also do the small 1uF electrolytics in the power supply on the boards that are soldered into the main PSU board?
So far the power supply and Reference are done, the rest to follow later.
Mine boots fairly quickly, under 30s. Maybe yours has a bigger base image for more complicated standards!?
I get DECT and GSM as options installed. I was thinking of backing up the compact flash card in case that wears out. If you want, I can send you the card image if I get round to dumping it into a file. it may speed up booting!
Wouter -
I can't honestly remember, but I don't think I knowingly left any out.
Meanwhile mine has a couple of other faults, I managed to blow up the N port but have no idea how, using the TNC aux connectors for now until I get around to taking it apart again.
Then at the weekend after it'd been on for half an hour or so the screen started getting snow on it with apparently bad writes to the screen buffer. It was particularly warm and humid at the time, it hasn't repeated this since. -
Sorry for digging up an old thread, but the I have quite similar issues.
I purchased today an Anritsu MT8801B which I was able to test as it powers up and opens all test apps.
However, when I started testing it to measure analogue FM-radios, I noticed it will freeze. No keyboard input will have any affect. The clock will continue to run, but that's it. No variation in measured power or whatever.
The unit is in decent shape, but all these problems are reappearing in analogue test sets, which are why I bought the unit in the first place.
Naturally, I will give the vendor a call tomorrow to see if there's anything to be done (it was the only MT880x there).
There were other symptoms too; the rf modulation measured at 100kHz (should be <5kHz) and there was no visible indication on the spectrum analyzer either.
Apparently, all these should be solved by changing the caps, but that'll be a few days work + parts. -
Till now, my unit is top-notch.
I am quite amazed how powerful and reliable analyzer is.
Analog measurement option is very precise and capable
to measure down to a few uVolts (very useful in measurements of hiss in audio preamps).
Also, RF generator is extraordinary useful in testing ham receivers (down to -143dBm)!
I am also thinking about back up the compact flash card,
unfortunately, haven't enough software knowledge to manage that.
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Are these units good for assessing RF amplifier performance, RF power, modulation etc. on the 88-108Mhz FM bands?
What about wifi bands 2.4ghz etc?
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Are these units good for assessing RF amplifier performance, RF power, modulation etc. on the 88-108Mhz FM bands?
What about wifi bands 2.4ghz etc?
They're fine for that, with the proviso that they won't demodulate the complex mod of the wifi -
Ok I ordered a 'tested' unit off ebay for $600 with the S.A. I hope all is well when it arrives.
thx
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I got here a sick MT8802A with SA option 07 on my bench. It boots to an error "System error! 33". I followed the service manual and enabled on the back of the front panel one dip switch for verbose mode and this showed more Information: The ATA card error (see pic) revealed that the 20 MB PCMCIA ATA card is obviously dead. Looks like this card contains some very important files for the boot process. The PCMCIA card is hidden under a small metal cover fixed with 2 screws and easy accessible from outside on the rear of the device.
I have a reliable PCMCIA Reader with my PC and this PCMCIA card is definitly dead. I have some other PCMCIA ATA flash cards with similar age and they are all working properly.
It would be a great help, if MT8802a owners could create a disk image (I use Win32diskimager) of his working card and could share it. A backup is always useful. I dont want to abandon this great TE already now...
Thanks in advance for your Support.
PS: Yahoo Groups holds already an old thread regarding MT8802, but i didn't got a reply yet.
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It would be a great help, if MT8802a owners could create a disk image (I use Win32diskimager) of his working card and could share it. A backup is always useful. I dont want to abandon this great TE already now...
I don't have an MT8802A but if it works like on other Anritsu gear then the card will not only contain the software but also the license codes that enables the software to work on your specific unit.
Good luck! -
I got here a sick MT8802A with SA option 07 on my bench. It boots to an error "System error! 33". I followed the service manual and enabled on the back of the front panel one dip switch for verbose mode and this showed more Information: The ATA card error (see pic) revealed that the 20 MB PCMCIA ATA card is obviously dead. Looks like this card contains some very important files for the boot process. The PCMCIA card is hidden under a small metal cover fixed with 2 screws and easy accessible from outside on the rear of the device.
I have a reliable PCMCIA Reader with my PC and this PCMCIA card is definitly dead. I have some other PCMCIA ATA flash cards with similar age and they are all working properly.
It would be a great help, if MT8802a owners could create a disk image (I use Win32diskimager) of his working card and could share it. A backup is always useful. I dont want to abandon this great TE already now...
Thanks in advance for your Support.
PS: Yahoo Groups holds already an old thread regarding MT8802, but i didn't got a reply yet.
Let me see if I can do that this weekend. I have an old Dell D820 laptop that has a PC card slot, hopefully that will be able to read the instrument's PCMCIA card. -
@howardlong: That would be really great! Thanks for spending your time in this! I hope file size after compression is not too big. What brand of flash Card is in your MT8802a? I have a IOdata PCFCA 20m Pcmcia flash ata card. It's from 1999 and basically based on Sandisk.
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@howardlong: That would be really great! Thanks for spending your time in this! I hope file size after compression is not too big. What brand of flash Card is in your MT8802a? I have a IOdata PCFCA 20m Pcmcia flash ata card. It's from 1999 and basically based on Sandisk.
My card is a 20MB Sandisk. Win32DiskImager used, v0.9.5.
https://1drv.ms/u/s!Ak3HU3AygNouhJEh2B61S_9hoOdGxg
