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eHam Forums => VHF / UHF => Topic started by: K9GRZ on September 26, 2017, 04:53:04 PM



Title: QYT KT8900 SQL or COS tap
Post by: K9GRZ on September 26, 2017, 04:53:04 PM
I need a SQL or COS signal and this radio doesn't provide it on either the data port or the mic.  Is there somewhere inside where I can tap in and bring out a line with this signal?  I could probably find it if I had a schematic, alas, I don't have one!

Thanks and 73


Title: RE: QYT KT8900 SQL or COS tap
Post by: K4JJL on September 27, 2017, 06:49:53 AM
Does it have a busy LED?


Title: RE: QYT KT8900 SQL or COS tap
Post by: K9GRZ on September 27, 2017, 07:13:45 AM
Unfortunately, no.  No busy LED.


Title: RE: QYT KT8900 SQL or COS tap
Post by: K9GRZ on September 27, 2017, 04:38:47 PM
 :)
Well, well.  Never mind!  The manual (such as it is) is incorrect and pin 2 on the mic plug appears to be a SQL signal at +3 volts normally, drops to zero when a proper signal is received.

Using Menu 51, REP-M, one can set the "proper signal" to a simple carrier, CTDCS, Tone, or DTMF.  Or off if it's not being used (pin 2 is still at +3 volts even when this function is not being used).

It appears this gives me exactly what I was looking for.  Now to get it all wired up and see if it works.