>changed 500zg amp's to rfp'.
>idle current increased 0.18 to 0.28.
>is 0.28 unusual or not ?
>
? A ZSAC of 0.28A usually means that the 7.5v, 10w zener is shorted.
This occasionally happens during the TL-922's intermittent
parasitic-oscillations at c, 120MHz. The zener can be replaced with a
series of c. 8, 1A rectifiers [arrows opposite direction for forward bias
instead reverse/zener bias]. The bandswitch contacts may have been
burned during the parasitic. [see page 33 of "Parasitics Revisited" in
the October 1990 issue of *QST* for a photograph of a VHF parasitic-arced
TL-922 bandswitch]. Improved parasitic suppressors and glitch
protection may help prevent future damage.
cheers, Shigeo
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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