Moment of Truth: Difference between revisions

From Collins 30S-1 HF Amplifier
Jump to navigation Jump to search
No edit summary
No edit summary
Line 3: Line 3:


But nothing happens other than the metering lights illuminate.
But nothing happens other than the metering lights illuminate.
After 180 seconds the metering lights illuminate indicating that the prerequisite time to warm up the 4CX1000A cathode has elapsed and it is now OK to turn on the high voltage.
After 180 seconds the dial lights illuminate indicating that the prerequisite time to warm up the 4CX1000A cathode has elapsed and it is now OK to turn on the high voltage.
Check the filament voltage and it is 6 VAC+ (since no tube has been installed at this point)
Check the filament voltage and it is 6+ VAC (since no tube has been installed at this point)
Check the bias voltage and it was adjusted to -80 VDC.
Check the bias voltage and it was adjusted to -80 VDC.
All other readings of the multi meter are zero. So far so good.
All other readings of the multi meter are zero. So far so good.

Revision as of 22:53, 21 May 2020

Working, restoring, rebuilding, checking, validating all seem to be fun. Each step of the process is thought out and the expected result is a function of ones skills in performing each step. But turning on the power. Well. For some reason the adrenaline increases. The heart rate goes up. One stands back from the open enclosure to prevent personal injury should there be a flash over.

But nothing happens other than the metering lights illuminate. After 180 seconds the dial lights illuminate indicating that the prerequisite time to warm up the 4CX1000A cathode has elapsed and it is now OK to turn on the high voltage. Check the filament voltage and it is 6+ VAC (since no tube has been installed at this point) Check the bias voltage and it was adjusted to -80 VDC. All other readings of the multi meter are zero. So far so good.

Now. Turn on the high voltage. Again. Nothing happens! Check the HV reading and it indicates +3200 volts.

The heart rate starts to return to normal. I reach for a cold one. That Coke sure did go down smooth!