I have an 8652b with spurs at -70dBc.
In your experience are there any caps which are especially at risk
of failure?
I have not, yet, opened it to have a look and make measurements.
Thanks
On 22/04/20 08:46, Peter Hansen wrote:
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Hello Stu be very carefull if you will recap the psu. It is an
old brittle 4 layer board. solder joints does need alot of heat.
You can easy ruin the connection to the middle layer. The 3
legged cap is still only a normal capacitor just with an extra
leg for support. As I said before put in a 220uF cap and try it
out. Do not attempt recapping anything before the problem is
solved. You might end up with multiple powersupply failures.
Also it is very easy to explode the main Fets in the PSU. so
work carefully.
Finally I will say recapping is only due if you see spurious
signals around the center response.
That can only be seen with the alulid mounted over the PSU.
The 28V is used all over in the RF circuits that is why you see
errors.
So Stu why don?t you just start with changing the Cap. Use a
220uF 40-50V 105degree capacitor (no china crap)
best regards Peter
