Batboard

Hi,
I'm having a problem with this MSF. No indicator lights is the most obvious symptom...however, after checking pretty thoroughly...I have good A+ in and good 9.6v comin' off the IPA. What I don't have is 5 volts on the control tray. If I temporarily lift jumper Ju8 , I'll get indicator lights...that tells me that the 5 volt supply is good and the short is somewhre down the to the right of Ju8. Maybe you've had a similiar situation you would like to share with us?

Help!

Bill

You might read this article:

http://iwce-mrt.com/ar/radio_finding_sh ... /index.htm

Also, the HP current tracer probe is one of the handiest tools you can have in your bag of tricks. These things cost $975 in the 1996 HP catalog.

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... gory=50971

do an search under msf 5000 i seen a string about this a while back ill see if i can find it

Check the RED filter caps on the P/S board and on the Main Board.. Had same problem awhile back and changing these caps cleared the problem.

My two bits worth:
You don't mention which model, but I presume that it is the analog station.
The filter cap to replace is the one with the red epoxy end next to the switch transistor.
there is an identical unit on the interconnect board under the
RF casting. Replace that one too.
This is a known failure item, and these are also in the R2001B/C analyzers, and they must be replaced.
There is also another cap next to it, replace that one too.
It can cause over heating of the switch.
These caps overheat because of the RF nature of the switching supply.
While you have it apart you can "loose" the shield over the switch transistor. All this does is cause over heating, and early failure of the switch. Later units omit this part.