>
>Larger tubes such as a 4CX3000A require very little drive power, but the
>required grid voltage swing is very high.
>What is the proper or most commonly used method of deriving this voltage
>swing from the standard 50 ohm driving source? I have not looked at the
>data sheet lately, but believe its over 200 V P-P for the 3x4.
>I have justed started looking at this reflector. Can anybody help?
>
? The drive requirement is about 230v peak. Briefly, the
4CX3000A/8169 grid requirement can be met with a bifilar 1-to-4 step up
broadband toroidal transformer, a 200-ohm grid. term., and c. 150w of
drive. Details are on my Web site, in "Amplifiers". The last amplifier
I built was a general-coverage 8169 in grid-driven neutralized Class AB1.
- I observed some disadvantages with the 8169:
1. The best socket (the y-330b) is not cheap.
2. The smallish anode cooler required a high-pressure blower that was
not cheap.
3.. The 8169 has No handles
4. .The 8171 has Way more emission, cools easier, is less expensive, and
it has handles.
- good luck, Bruce.
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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