Author: wlfuqu00@pop.uky.edu (William L. Fuqua III)
Date: Tue, 5 Oct 1999 09:07:34 -0400 (EDT)
Just bought a HB amplifier. A pair of 4-400 in GG. It looks very nice but a few things I see need to be changed. This one is just fine except for the following: 1. Clip on plate caps of the type usua
I once replaced one in a 4-1000A amp owned by an OT. He told me that every few years he had to replace it! The switches were cheap and he got guys like me to do the work. The current-carrying capabil
? The BC375 switch has a very substantial voltage withstanding ability because it was designed for high altitude operation in unpressurized aircraft. The (high-Mu) TH is the only version that will w
Hi Bill, the following observations are based on using a similar GG 4-400 amp for about 30 years: No problem, works fine with adequate side cooling. This works fine as long as plenty of air is moving
This has a muffin fan. But I guess he did not run it at higer powers. Glowing plates. The main problem being the heat conduction thru the plate lead to the seal. I'm concerned about cracking the sea
Sounds to me like you already made up your mind that it's no good. Why did you buy it? Why did you ask if it was OK if you already believed it was not. It also sounds to me like you have never run a
Author: wlfuqu00@pop.uky.edu (William L. Fuqua III)
Date: Thu, 7 Oct 1999 08:32:34 -0400 (EDT)
Ok so much for the personal insults. If you wish to do that e-mail me in directly and I'll either ignore it or reply. That is one thing I really don't like about this list. I asked for opinions? I ha
Author: wlfuqu00@pop.uky.edu (William L. Fuqua III)
Date: Thu, 7 Oct 1999 09:51:44 -0400 (EDT)
I got an urgent call from the office and planned to save the previous e-mail and finish it when I returned. However, in my haste to leave, I hit the send button by accident. I'll wish to continue: I
Hi Guys, One thing you might want to be careful of when mounting Anode coolers, is to lift the metal heat dissapator slightly off the glass of the tube, before cinching down the set-screw, to prevent
Certainly a reasonable precaution with tubes like 813's. Not a problem with 4-400 class tubes. Take a close look at one, you'll see why. 73, Larry - W7IUV w7iuv@arrl.net http://www.axtek.com/w7iuv Am
Sorry guys, but I couldn't pass this opportunity to interject here: Clandestine operations with an acytlene torch produce interesting conversation pieces and dandy old wives tales. Try as hard as I c
Hi Larry, et al.... I don't understand....Oh, perhaps what you are talking about is a different type of plate cap....My 4-400s have simply a metal rod, about 1/16' dia coming out the top...right out
I have not seen it either. I have seen the EIMAC ad however. Also an earlier ad with a hole melted in the anode of a 250TH I think. If no one on this list has seen a hole sucked in the side of a tube
I can't speak for real RF power tubes, but I melted a 6KD6 sweep tube in my old Yaesu FTDX-560 that way. Clear evidence of melted glass, followed by an implosion, leaving a window in the envelope. 73
Pete, I'm interested in this experience of yours because I was never able to purposely get a tube to do that. I always experimented with small tubes (spell that c-h-e-a-p) of similar size. I could ea
Hmmmm. Interesting. What brand tubes do you have, Pat? I have maybe 18 or so around here. Eimac's, Penta's and Amperex's in the bunch. All of them have the larger cap set screwed to the (Kovar?) ano