Bill Turner wrote:
>>Does the 91 have an inductance in series with the grid termination R? If
>>so, how much L? What is the value of the GTR?
>>thanks
>>Rich---
>>
>_______________________________________________________________
>No coil in series with the grid terminating resistor. From the
>grid(s), there is a 1 mHy coil to the bias supply, a pair of .02 mF
>caps in parallel to the GTR, and from them, the GTR directly to
>ground. The GTR is 50 ohms, 90 watts. The cathodes each have a 12
>ohm 5 watt resistor directly to ground, with nothing else. The
>cathodes are not connected to the heaters. Each tube has its own
>anode suppressor, each one is a pair of 220 ohm, 2 watt resistors in
>parallel with a coil of unknown inductance. There are no other
>suppressors such as ferrite beads, etc, visible on the schematic.
I have the schematic, but unfortunately not the amplifier :-)
There is a small inductor switched in series with the 50-ohm input for
24 and 28MHz, but it isn't connected between the grid resistor and the
grids.
BTW, please can someone who owns a 91B confirm that it does NOT have
screen grid (G2) current metering?
73 from Ian G3SEK Editor, 'The VHF/UHF DX Book'
'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.demon.co.uk/g3sek
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