[Heathkit] power supply problem on a SB-401

[wa9vrh]

Hi Dale,

I forwarded your message to Tom from Hayseed and he asked me to send you 
this information.

Can of C79 (the forward one) should be grounded to chassis.  The 
original mounting plate should be steel.  Can you pass this along for 
me, Larry?  Tnx.

Hope this helps.

73 Larry WA9VRH


On 8/12/2012 2:49 PM, yash at aol.com wrote:
> Just replaced the 2  - 125 mfd  caps in the high voltage supply. These were new from hayseed co, made to order . also replaced the 2- 100k 3 watt  resisters  and the 500k and 10 k resisters. double checked ALL the wiring against the schematic and the heath pictorial drawing. all checks fine. If I measure the output off the diode string I get about 695 +vdc. If I check the voltage at the output of the second filter cap ,I get about 280vdc. should be 700+ vdc. If I switch the meter to high voltage, the meter pegs to the right and I get a pulsing noise as the needle bounces off/on  the stop pin.  the other voltages from the supply are ok. I get 300 vac out of the transformer between the red and red/yellow leads. the 2 big filter caps float above ground via the plastic wafer mounts they are mounted on.  this is a full wave voltage doubler circuit,so will end up with the 700+ vdc. There must be something Iam missing ,this is a simple circuit .
>      Any chance ,the new custom caps from hayseed could be bad?
>    Have spent 3 hours on this  and ??
> thanks for any help.
> dale wt4t
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