I am attempting to calculate the Pi-L tank values for a GS23b HF amplifier I am building and I am a bit confused. I know this tube is usually used at VHF and above but OM power does use one at HF and
David, at the risk of over simplifying a complex issue, some thoughts: With a low loss matching network, the tube efficiency is primarily related to the class of operation. Class C can be 75%, class
Hi Dave, you might give my "RF Tube modeller" application a try. It will easily calculate a.o. efficiency, Rload and other parameters. All based on the constant current graphs as provided by the manu
Thank you all for the responses. Carel I have seen your site and I will try your tube model software. Jim, I agree on stray capacitance, I am using a value of 5pf for the estimate but that's a pure g
Dave and All, GS23b is the greatest Russian tube, it is not so known as GS35b, GU74b or GU84b due to its socket, it is impossibly to find industrial ones and it is very hard to build GS23b quality so
I got a socket from a ham in Slovakia (Homemade), Branko S52V, and he did a very nice job on the socket with copper finger stock. I attached a small picture. Have not yet of course used it but the tu
ORIGINAL MESSAGE: (may be snipped) REPLY: For what it's worth: I have built two amps using the GS35b and had the same low efficiency you indicate above. Several European hams have reported the same.
ORIGINAL MESSAGE: (may be snipped) REPLY: Yes, I always use a tuned input on my amps. Design Q for the output tank was 12 per the G4AXX spreadsheet. You might be interested to know that in both amps,
Bill, Thanks for the update. I think the GS35b is a lot like the general soviet style of the time - big and functional, but not very elegant. ha ha. It's not a great tube functionally, but it looks c
Efficiency goes up with higher anode voltage. With a 2m push-pull and 4KV on the anodes we obtain 60% easily (5 out)at the DK3EE EME station. 73 Peter Bill, Thanks for the update. I think the GS35b i
Since we are limited only on output, it does not make much difference whether the amp is 50% or 60% efficient - especially in the winter. More amplifier loss means more heat in the hamshack. Instead
ORIGINAL MESSAGE: (may be snipped) REPLY: Like most things Soviet, it is built like a tank in the best sense of the word. Check out their doorknob capacitors. Superb. 73, Bill W6WRT _________________
ORIGINAL MESSAGE: (may be snipped) REPLY: For best results, mount the amp on a gimbal so you can direct the heat as needed. In the summer, you turn the amp on its side so the heat blows out the windo
load To Dave: The spreadsheet does NOT predict the efficiency the tube. In that part of the spreadsheet, efficiency is an INPUT value that you provide, and its accuracy is only as good as your perso
Yes I agree and that is what has me guessing, I donšt have a load line for the tube in HF service and since efficiency is a input value I donšt know if 50% or 60a5 or some other number is correct and
ORIGINAL MESSAGE: (may be snipped) REPLY: That's good to know Ian, but the spec sheet I have says the max DC is 3kV and the max instantaneous peak is 6kV. I'm sure those values can be exceeded a cert
ORIGINAL MESSAGE: (may be snipped) I think the GS35b is a lot like the general soviet style of the time - big and functional, but not very elegant. ha ha. REPLY: Like most things Soviet, it is built
What BDV does the GS35b typically show on "good" tubes? 73/jeff/ac0c www.ac0c.com alpha-charlie-zero-charlie ORIGINAL MESSAGE: (may be snipped) There is a major difference between the Western high-mu
OK, I bite: what is BDV? 73, Gerald K5GW In a message dated 10/31/2013 9:33:39 A.M. Pacific Daylight Time, keepwalking188@yahoo.com writes: What BDV does the GS35b typically show on "good" tubes? 73/
Lot of names. Hi-pot value. Break down voltage. Leakage test threshold. Its the voltage where the tube starts leaking current. 73/jeff/ac0c www.ac0c.com alpha-charlie-zero-charlie OK, I bite: what is