|
Title: Collins 32S3 low output Post by: WB8PFZ on December 10, 2022, 05:39:15 PM Hopefully this is allowed here. Good plate voltage, 200 mills of plate current 35 watts output. I can run the plate current higher but output seems low. Could the coupling cap from the plates to the output circuit be bad? Thanks Mike
Title: Re: Collins 32S3 low output Post by: Detroit47 on December 11, 2022, 10:52:40 AM I have to ask the obvious. What mode is the power down in? CW SSB? What is considered normal power? Do you have sufficient grid current. In short we need more data.
Johnathan N8QPC Title: Re: Collins 32S3 low output Post by: WD5JKO on December 11, 2022, 11:18:16 AM Yes, I agree with Jonathan, need more data!
However, lets assume a bunch, and if you have 700v B+ at 200mA, that is 140 watts DC input (ignoring if that is cathode current). With only 35 watts going out the rear spigot (SO-239), that means over 100 watts is being dumped in heat. Do the tubes glow cherry red, or blush at all? Is there smoke? Does the plate meter start to rise upward after about 15 seconds? How about changing bands to 40m or 20m, where the Pi-Net network may not rely on fixed capacitors getting switched in for 80, or 160m (if equipped)? Jim Wd5JKO Title: Re: Collins 32S3 low output Post by: WB8PFZ on December 11, 2022, 12:00:14 PM I am tuning up in CW mode. It happens on all bands. At one point I believe it was working correctly. The tubes do show color after a while. No smoke. I would expect to see 100 watts. I see no grid current. I also have posted this on Eham and received some pointers. I am looking to see what is involved with getting to the transfer relay. May be a tough job? Thanks all Mike AMfone - Dedicated to Amplitude Modulation on the Amateur Radio Bands
|