Recent content by bgosper

Hi, I picked up an old 3 tube base amp from Kris called "Power Pump". It does about 225-250 watts with 3 watts in. Does anyone have any info/manual on this amp? Can't find anything for it... Thanks. 73

Ok, need help on this! I decided to do some rebuilding/updating on parts in this amp. There are 4 big filter caps (450v/320uf) in here. I unscrewed them and removed them before I took note of the +/- alignment. 2 are chained together and the other 2 are chained together. Can someone take a...

Checks on the main board show about 15VDC in RX. With full modulation on SSB drops to 13.8-14.

Well like I said before, all the suggestions on here are all good and worth investigating. As far as the PS in this radio goes, should not be an issue. I rebuilt it myself several months ago with beefed up parts. Actually had a bit to much coming off the board and had to scale it back. And...

Ok, thanks. I have an old Kris Power Pump that does about 250 peak so I don't think an extra 50 is gonna entice me to buy!

Hi, Does anyone have any info on a Thunderbolt 305 base amp? How many watts do they do and what is tube configuration if known...? Thanks!

Hi-yes the shield is there on the freq counter box. I tried moving the amp further away but that did not change it. I had to order some toroid cores so I will have to wait on that. What concerns me is that I had the amp for almost a year with everything in the same spot and essentially unchanged...

Also, what do you mean by better RF bypassing? Thanks!

I lot of different ideas on this thread, all are speculation. I will try the chokes and spacing issue first since those are the "easy fixes"...thanks for the feedback.

Hi-thanks for the info. It is a PAL 750B base amp. Uses 9, 8950 tubes-I believe 1 drives 2&3 and they drive 4-9. . About 800 watts out on high with 2 watts in. I will try the coax lengths and see if that helps...

Ok, that also sounds like a viable reason though I do not have another radio to confirm with. Let's assume it is, what would be the cause of the high SWR between the amp and radio and the wattage loss caused by having the amp in line even if turned off?

UPDATE: The input SWR (between the radio and Amp) IS high-around 2.5 that includes with the amp turned off. I changed the jumpers but that made no difference. SWR between amp and antenna is normal--1.3 or so. Perhaps then this is the issue? Not sure what would be causing that though. Perhaps...

I agree...! Any ideas on how to diagnose/stop that? Again, it was never an issue until recently...

Jeff, I will check that. One thing I notice is that the output from the amp when it is totally turned off is about 1/2 of what is going into it from the radio. Another words, I use a about a 2 watt carrier out of the radio and into the amp. If I check the wattage after the amp, it is down to 1...

LSB mainly...