Tektronix TDS 3032B - Dead power supply

[Arca]

Hello all,

I picked up a broken Tektronix TDS 3032B.

PSU is dead on it (NFN40-7615N01 - https://docs.rs-online.com/f3f9/0900766b800a6f33.pdf). Some componant are dead (red on the picture) :



It seems that some componant had already been replaced in the past. There is also componants that I cannot identify (burned resistor for example), so I'm thinking about replacing all the PSU board by a new one, and not just replace dead componants (there is probably more dead componants than what is visible).

What reference could be compatible? The one that is used no longer exists.

Artesyn LPS64 could be fine ? https://docs.rs-online.com/34b4/0900766b814344f9.pdf

Thx

[giosif]

From the perspective of electrical specifications, I think LPS64 should be fine.
Even from the physical dimensions, it is ok, except for the height: it is about 1.0 cm taller than the original power supply.
Whether that extra height is an issue or not, I cannot say for sure, but I think it might interfere with the module plastic tray which normally sits above the PSU.

The other concern is the height of the heatsink and capacitors at the end of the board on the secondary side of the PSU, which might interfere with the board which has the Ethernet port (among other things).

I suggest putting the dead PSU back in the scope and put everything together, including the module plastic tray, but except for the rear case.
Then, check for clearance between the PSU and the surrounding elements.
If you have 1.0 cm or more of clearance, you are good with the LPS64.

[Arca]

Thanks a lot for your answer ! 😄

I'll check dimensions when I have a bit of time.

I'll give a feedback then.

[Arca]

Hello,

I'm about to order the board but yeah, LPS64 is a bit high and also expensive.

I found LPS44 with similar specs, less high and less expensive : https://fr.rs-online.com/web/p/alimentations-a-decoupage/1829997/

If I'm not wrong, it should work.

I also found a low cost one : https://fr.rs-online.com/web/p/alimentations-a-decoupage/0200055/

I guess the output connector is different but if I adapt it, could it work ?

Thx

[giosif]

The LPS44 looks to be an exact match, both electrically (in terms of output specs) and physically.

I didn't check the low-cost PSU, but I wouldn't risk the rest of the scope by going cheap on the power supply.

Good luck!