¿ªÔÆÌåÓý

  1. TekScopes2
  2. Topics

2465B - Replaced RIFAs and now won't POST

 

2465B
s/n 57xxx
When I first powered it up, the lights would all come on for a split second, then they would go out, then it would cycle through the self-tests, failing at TEST 05, so I cleaned up the A5 corrosion and replaced a few components there. I also replaced the RIFAs on the power supply.
Following that, when I turn it on, the lights all come on, but they don't go out.
All J119 points are well within spec. I am a little confused at times when following the service manual, for example the troubleshooting procedure said TP201 should be +10v, but the schematic seems to indicate it should be +5v, which is what I'm getting.
I'm not sure how to proceed at this point. I'd like to go as far as possible before I am forced to buy a new oscilloscope to repair this one.
Thanks
 

Have you worked on one of these before??
?
ISTR that there's a misprint on the silk screen showing a supply filter cap in the wrong orientation...
I know someone who recapped his 2445B and it didn't work after that - I have it in my stack of things to fix... Quite likely a problem with a board interconnect...
?
...which reminds me: The 2465B PSU has fragile interconnecting pins - Are they all ok??
?
?
 

Bobert29,
My thought is you need to check the plug connectors on the side of the A2A1 board J121 and J122 as you might be one pin off from connector to board. These plug connectors are not easy to see when plugging connector to the board.

Craig
 

¿ªÔÆÌåÓý

Hi? When I was 16, (74 years ago ) I worked on a US schematic to build a power amplifier,? 2 feedback capacitors electrlytics were designed in wrong polarity . connected between the tubes plates ..400 V and? cathodes close to ground. It did work some time, but eventually there was an explosion... And the amp cease working.? Just because the cap of the electrolytic was thrown away and its connecting wire short circuited the Hi Volt to ground..

Do not try to connect lmytics inverted...!


Jean? L? C? Ruelle
De :[email protected] <[email protected]> de la part de Craig Cramb via groups.io <electronixtoolbox@...>
Envoy¨¦ :?lundi 21 avril 2025 13:14
? :[email protected] <[email protected]>
Objet :?Re: [TekScopes2] 2465B - Replaced RIFAs and now won't POST
?
Bobert29,
My thought is you need to check the plug connectors on the side of the A2A1 board J121 and J122 as you might be one pin off from connector to board.? These plug connectors are not easy to see when plugging connector to the board.

Craig

1 - 4 of 4