Hi all, Ok, so lets do that, 4 x GU81 grounded grid configuration. Anyone has a schematic to follow? What levels could be fine? Thank you 73, Maximo - EA1DDO _________________________________________
How about push pull parallel grounded grid? But 4 in parallel would make for much simpler matching network. 73 Bill wa4lav _______________________________________________ Amps mailing list Amps@conte
As the suppressor grid is normally grounded and serves as a shield to prevent secondary emission, how would this affect running the tube in grounded grid...if at all? I would think it would tend to l
4XGU-81 in GG maybe need 300W driving power or more. GU-81 seems not good in 15m or higher band.But I have no experience on it. 73!Hsu As the suppressor grid is normally grounded and serves as a shie
As the suppressor grid is normally grounded and serves as a shield to prevent secondary emission, how would this affect running the tube in grounded grid...if at all? I would think it would tend to l
Suppressor grids have very few wires per inch compared to the control grid or even the screen grid. The primary electrons from the cathode should be not be affected enough to be an issue. Secondary e
Hi all, I found a schematic with GU81 grounded grid. What you think? http://ru3ga.qrz.ru/LAMP/200401.htm By the way, How much output power can we expect from GU81 GG ? Thanks 73, Máximo - EA1DDO ____
Here is the info you need: Specification Model number: GU-81M Manufacturer: Reflektor (Russian) Max anode dissipation: 450 W Max g2 dissipation: 120 W Max g1 dissipation: 10 W Max g2 voltage: 600 V M
Data sheet: http://danyk.wz.cz/gu81.pdf Or 600 W momentarily. Rated Plate voltage is 3KV below 6 MHz, 2.5 KV below 24 MHz and 1.5 KV below 50 MHz These tubes are regularly abused <:-)) Rated at 750 n
Hi all, I am already starting this project. Just a begginers question. Remember it is 4 x GU81 Grounded grid. Filament transformer. It is 12.6VAC around 11A each tube. Should I use one transformer pe
Hi all, I´ve been told that I can use DC for filaments (instead of AC), Is that true? If it is true, Can I use switching power supply for filaments? Tubes GU81 needs 12.6 v and around 10A, I could us
You can always use DC on an indirectly heated cathode, but with a directly heated filament you must consider the fact that one end of the "cathode" will have 12.6 Volts more or less cathode to grid b
If you have AC supply the emmissive current would have to be added to get the total filament current. That is because it is not the average current but the RMS current that heats the filament. We don