Here we go with a Brand Z 9-S-262
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City: Ferdinand
State, Province, Country: Indiana
(01-18-2015, 02:07 AM)Arran Wrote: Whilst it seems like tube stuffing a chassis on brand Zs part having separate oscillator and mixer tubes is actually a meaningful improvement to a radio. Having separate tubes for the mixer/detector and local oscillator reduces noise and allows more stable operation at higher frequencies then a pentagrid converter like a 6A8 or a 6A7.
Acked, and agreed. Philco did their own cost-cutting, though, and from 1932 on it usually involved combining mixer and oscillator functions in one tube, poorly at first (the infamous autodyne circuit first used in the late versions of the 70 and 90, then the 51, 52, 15, 71, 91 and most infamously, the 19 and 89). The 6A7 was a big improvement over using a 36 tetrode. But, yes, separate mixer and oscillator is always better. So Brand Z gets points for that.
But I take away points for connecting a 6H6 as a single diode (both plates and both cathodes are connected together, making it a single diode). Again, a 6Q7G could have done the same job as separate 6H6G and 6F5G tubes did.
Oh well, a 9 tube radio sounds more impressive than an 8 toober, right?
--
Ron Ramirez
Ferdinand IN
Messages In This Thread
RE: Here we go with a Brand Z 9-S-262 - by Ron Ramirez - 01-18-2015, 09:34 AM
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