[Boatanchors] HT-fB Problems

[Barrie Smith]

Hello:

I have not used my HT-4B for several years I've decided to get it 
back on the air this winter. I attempted to fire it up today, but 
no luck.

I have AC. I have all the normal driver stage currents. When I 
apply high voltage I get a dip in plate current, but it dips to 
about 40 ma.

If I tune off resonence, the plate current climbs to 150 ma and I 
get a red plate in the 250TH. This indicates to me that I have high 
voltage, and possibly drive.

Using a receiver in the shack, I get a loud carrier from the driver 
stages.

The push-to-talk does not work. Usually, in the past, I get a loud 
relay "clunk" when I hit the push-to-talk. That is now missing.

I checked the switch in the microphone and it's less than one ohm 
when closed.

The antenna relay does not actuate when I hit the push to talk.

I have idling plate current on the modulator tubes, as indicated by 
the meter in the transmitter. However, It does not show on the BC-
614E meter.

All of this indicates a problem with the cabling between the speech 
amp, or a relay in the transmitter.

Before I chase my tail all over town, anyone have any ideas?

73, Barrie, W7ALW



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