[AMRadio] WTB: WRL Globe King 500-C (or A)

[wwd at netheaven.com]

>>Just where does one find V70D tubes, though?

All you need is a working pair of triodes, don't even have to have
'matched' output. If one tube is weaker than the other, just place it on
the side that does not require as much power. This will depend on your
audio chain phasing. Usually with the male voice the high peaks are on one
side of the mod transformer. Switch tubes to find out.

ANY triode in the 65 to 150 watt plate dissipation should work in place of
those impossible to find V70Ds. Set bias as required for that particular
tube. You can even use tetrodes- just connect the screen grid to grid-
"screen-driven triode-connected" mode. Here though it would help to ask
someone who has actually one it.  

Never pass up a nice pair of triodes for a decent price, even if you are
not familiar with the tube number. If you can see it is a triode and if
the fil continuity is good using your pocket VOM, grab em.

5514, HK-54, 806, 838, HF-100, 254, T-55, 8005, HF-201, 805, 203-Z, T-40,
TZ-40, 810, 811 & 811A, HF-150, 830-B, 211.

8000 and 812 are better for rf duty rather than modulator, but can work
fine if you can get the bias set right.

I mentioned 5514 first since I think it is very close in P-diss to the
V70D tube. Even has the grid cap on the side. Most tube collectors will
pass it by, so remember that #.        8-)

Bill    K2AME

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wwd at netheaven.com  To the warriors go the spoils of war; to the hindmost .  .  the surplus.
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