Author Topic: Anritsu MT8802A boot problem  (Read 1663 times)

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Offline Radio TechTopic starter

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Anritsu MT8802A boot problem
« on: December 30, 2021, 11:42:11 pm »
Hi all,
Been quite a while since I posted here.
Recently gifted an Aritsu MT8802A radio test set.
There is an issue with the unit but I do not think it has a software problem.

Possibly bad connections, capacitors or even dead battery. .  I will be tearing into this unit soon but just wanted to see if anyone had seen this problem on one of these.

When power up self test shows SRAM battery empty.  Then after self test it goes to a blank screen and beeps, also panel lock light comes on.
If you turn off and turn back on while pressing the "Preset" button the unit loads up and works fine.

The person that gave me the set also gave me a complete capacitor kit for it.  Will probably start with pulling boards, visual inspection,  and cleaning connectors while replacing anything that looks dodgy.  And of course video the process anolng the way.

I did find another interesting thread here on the forum but it is very old and instead of posting to that one I just made another since it is a different issue.  The last post on the thread desribe my symtoms that I am having but there were no further replies from it.

Just looking to see if anyone had experienced this issue.

Time to get started...
 
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Offline oz2cpu

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Re: Anritsu MT8802A boot problem
« Reply #1 on: December 31, 2021, 12:12:22 am »
i got an 2802A for free, defect, trash loot
all electrolytics in the entire unit puked all over all boards, tracks etched away, and what not,
took me a month full time, to repair it, yours must be same age..
so i assume you got, or will have same problem soon,
you better take a lot of pictures of all details while you take it apart, write notes, on all wires and connectors,
also note on mecanical parts, where they are located and orientated, numbers, lines, with a parmanent marker helps,
and screws are in many different length, note that too,
i took nearly 200 pictures, so i know how to put it back,
just ask if you want to see some more sad pictures ...
« Last Edit: December 31, 2021, 12:21:01 am by oz2cpu »
Radioamateur OZ2CPU, Senior EE at Prevas
EMC RF SMPS SI PCB LAYOUT and all that stuff.
youtube : oz2cpu teardown
 
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Offline Radio TechTopic starter

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Re: Anritsu MT8802A boot problem
« Reply #2 on: December 31, 2021, 12:43:22 am »
i got an 2802A for free, defect, trash loot
all electrolytics in the entire unit puked all over all boards, tracks etched away, and what not,
took me a month full time, to repair it, yours must be same age..
so i assume you got, or will have same problem soon,
you better take a lot of pictures of all details while you take it apart, write notes, on all wires and connectors,
also note on mecanical parts, where they are located and orientated, numbers, lines, with a parmanent marker helps,
and screws are in many different length, note that too,
i took nearly 200 pictures, so i know how to put it back,
just ask if you want to see some more sad pictures ...

Oh what a mess! Strange how much those caps leaked, even those being isolated and not sitting on the board.
Looks like you had your hands full on that unit.
I will give mine an inspection tomorrow and see if it shows any of the same damage, Really hope not but never know.

Seems this brand is missing a lot of service information.  I have yey to see any schematics and board layouts.
Appreciate you taking the time to post and share your information.

Offline Radio TechTopic starter

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Re: Anritsu MT8802A boot problem
« Reply #3 on: January 01, 2022, 01:32:24 am »
Got the boot issue fixed.
Just a simple battery replacement.
Next is to start the tear down and replace capacitors and clean contacts.






 
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Offline G0GCD

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Re: Anritsu MT8802A boot problem
« Reply #4 on: March 20, 2023, 05:18:45 pm »
Many thanks for the teardown video... I'm about 2 years behind you!
My MT-8801C has exactly the same boot issue and I'm getting ready to do the battery replacement, following your footsteps. What battery did you use to replace the Anritsu one? Could you extract a part number from the old battery to determine its capacity?
I'm planning to replace it with a CR2023 (in a holder)...

Did you find any leaky capacitors? did you completely re-cap the unit?

Did you move on to solving the low display brightness? Any pointers on how to do that with the minimum of disruption?
I'm planning on using a pair of LED 'tubes' to replace the CFLs in the display.

Finally, I've been advised to back up the PCMCIA card. Have you any experience of doing that little chore too?

Great, informative, video. Some others just drag on and on but you pitched your timing just right for me. Thanks!

Regards
John G0GCD
 


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