Hello Mark.
22 Apr 97 00:16, Mark Magill wrote to All:
 MM>         A fellow ham has a simplex autopatch up, using the * key to
 MM> open it and the # key to close it, as is common here. Problem is, he
 MM> tuned it (it's an old simpatch) using his HTX-202 as the test for
 MM> proper decoding. My standard ICOM 2-AT won't access it, neither will
 MM> his other handheld radio in later tests.
 Does that old simpatch use 556's as a tone decoder?  If so, you can tune 
them seperately by pressing two buttons in the same column or row to get a 
single tone from the HTX or the ICOM...  The tone deviation on the radio used 
to tune them should be =less= than the 5khz allowed.  Say around 3.5 to 
4khz...
Tone decoder's are pretty forgiving ( I don't recall the ñ% of tone 
tolerance, but it's wide). You should be able to tune it to allow all radios 
to access it.
... Old MacDonald had a computer, with EIA I/O...
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