[Hammarlund] Question/Help on SP-600 fuses

[bill riches]

Are you using a slo-blow fuse.  If you turn on the rig at the same time the
AC input waveform is at its peak it can blow a fast blow fuse.

If the fuse blows the instant you turn on the rig, pulling out the HV
rectifier should not make any difference as there is a second lag in the
tube filament heating and producing power to the receiver.

73,

Bill Riches WA2DVU
Cape May, NJ


Depending on the serial number the power line fuse for a sp-600 is 1.6 A
or 3A.
Why the difference ?

Now for the hard question: The sp600 I am currently working on
periodically
blows the 3A power line fuses at turn on. Once on the rig seems to run
fine.
Any suggestions for cause/trouble shooting ?

I'll pull the HV rectifier and see what happens.
If necessary check out the resistances again.

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