开云体育

Hi everyone,

Yesterday, while working with my Tektronix 2465, I suddenly heard a strange noise from inside, followed by a very unpleasant smell. There was no smoke, and the trace was still visible on the screen. I immediately turned it off and haven’t tried powering it on since.

I suspect it might be a Rifa capacitor gone bad, but I need to inspect the boards to be sure. After removing the cover, I realized that I can’t clearly see how to remove the A2 (Horizontal) and A3 (Vertical) boards.

My main question is: Can I remove the A2 and A3 boards without taking out the A1 (Main Interface) board first?
Or is there another trick to access them more easily?

Any tips or advice from those familiar with the 2465 would be greatly appreciated!

Thanks in advance!

On Fri, Feb 21, 2025 at 09:40 AM, <zheniak@...> wrote:

My main question is: Can I remove the A2 and A3 boards without taking out the
A1 (Main Interface) board first?

Service manual section 6-25 describes how to remove A2 and A3, it doesn't need removal of A1. If the construction is similar to 2465B I found that removing IEC power supply filter made access easier. I don't know if 2465 has the same filter.
Ozan

Aren't the likely Rifa suspects (C1016 and C1018) on the A2 board?

Thanks,
Barry - N4BUQ

Thank you Ozan!
I just got the manual. Indeed, there are instructions on how to do it.
Z.M.

The A2 and A3 boards can be removed by themselves and, I may be wrong about this, but I think loosening some of the screws on the back panel frees up a tab on one of those boards that slides into a hole the back panel.

Thanks,
Barry - N4BUQ

Not quite sure. They are visible without removing the board, and I don’t see any damage there. I’ll know better after removing A2."

Funnily enough I've removed and reinstalled several of these in the last couple of weeks.

My experience has shown me that there were two different types of fan used on these scopes. The earlier ones had the fan motor attached to the inverter board (with the two large filter caps) with a round fan protected by a metal plate, whilst the newer ones had a standard square-framed fan fixed to the rear of the scope.

The earlier ones need the fan removed first and then after removing a few screws on the rear panel, three from the lower heatsink, and disconnecting all the cables, it can be lifted straight up until the fan shaft nears the top of the rear hole, at which point the end facing the control panel needs to be angled and it easily lifts out.

The later ones just lift straight up and out (after screw and cable removal). They can feel like they're welded in but just make sure you keep it level and watch for the power cables getting in the way.

There are two Rifa's on the regulator board and three on the inverter board. All very straightforward to replace.

Good luck

I have found it's easier to loosen the collet holding the fan onto the
fan motor to do the removal. It can also be a good time to add some
silicone lubricant to the motor *if* it needs it.

On Fri, Feb 21, 2025 at 4:00?PM James55 via groups.io
<james_55@...> wrote:

Funnily enough I've removed and reinstalled several of these in the last couple of weeks.

My experience has shown me that there were two different types of fan used on these scopes. The earlier ones had the fan motor attached to the inverter board (with the two large filter caps) with a round fan protected by a metal plate, whilst the newer ones had a standard square-framed fan fixed to the rear of the scope.

The earlier ones need the fan removed first and then after removing a few screws on the rear panel, three from the lower heatsink, and disconnecting all the cables, it can be lifted straight up until the fan shaft nears the top of the rear hole, at which point the end facing the control panel needs to be angled and it easily lifts out.

The later ones just lift straight up and out (after screw and cable removal). They can feel like they're welded in but just make sure you keep it level and watch for the power cables getting in the way.

There are two Rifa's on the regulator board and three on the inverter board. All very straightforward to replace.

Good luck

Indeed
/g/TekScopes/photo/300835/3889065?p=Created%2C%2C%2C20%2C2%2C0%2C0

On Fri, Feb 21, 2025 at 01:58 PM, <zheniak@...> wrote:

Indeed
/g/TekScopes/photo/300835/3889065?p=Created%2C%2C%2C20%2C2%2C0%2C0

While you are at it, you should check the resistor in series with the blown RIFA, current limiting NTCs for drift, and the resistors in parallel with the NTCs for damage.

There are three more RIFAs on the other board if it is similar to 2465B/2467B.
Ozan