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Letter Tube Numbers XXL vs. 7A4 etc
#9

In early Philco books, I see the characteristics are slightly different between the XXL and the 7A4. Later books list them with identical characteristics. Like Randel, I have some XXL/7A4 branded tubes in my 42-350. You will not notice any difference. XXFM is identical to 7X7 so no problem there. FM1000 is unique and nothing replaces it. Another Philco equivelant is 14AF7 and XXD.

I built an FM converter off of Chuck's website. The pre-war Philco FM sets are just so-so performers. There is no limiter stage so they are sensitive to noise but it is neat to hear them play.

Fred


Messages In This Thread
Letter Tube Numbers XXL vs. 7A4 etc - by Guest - 05-11-2008, 01:52 AM
[No subject] - by Guest - 05-11-2008, 12:37 PM
[No subject] - by Ron Ramirez - 05-11-2008, 02:46 PM
[No subject] - by Guest - 05-11-2008, 07:25 PM
[No subject] - by exray - 05-11-2008, 10:28 PM
[No subject] - by BDM - 05-11-2008, 10:36 PM
[No subject] - by Texasrocker - 05-12-2008, 01:55 AM
[No subject] - by Fred R - 05-13-2008, 07:01 PM



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