How can I use the 8 pin CAT connection to activate a SDR switch?
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Looking at the diagrams I tried using pin 2 (circled in red) to activate the switch. I was under the impression it was grounded while the radio was transmitting. I checked with a DMM there is no continuity between the wire attached to pin 2 and the chassis of the radio. Pin 3 shows continuity on the DMM.?
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I'm using a splitter so I can run my digirig and the switch. I verified proper operation of the switch by manually grounding the wire to the power harness of the SDR switch.?
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I also verified multiple times that the wire I'm using is pin 2.
?
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Am I doing something wrong ? Is there a better way? The switch is looking for a momentary ground while transmitting.? |
开云体育Pin-2 of CAT (TX-GND) is not grounded until signal line TX-B at the base of Q1108 is brought HIGH (>0.7V, 5V I think), forward biasing B-E and B-C.?
i presume because CAT is multipurpose depending on menu settings, so you want that line grounded only when MCU decides it should be.
Michael Boatright, M. Photog., CPP, GSD
Michael Boatright Photography 404.488.6644 Portraiture & Documentary Photography Historic Wet Collodion Process Goat Farm Arts Center 1200 Foster St., NW, Suite S301 ATLANTA, GEORGIA 30318
FB: IG: Certified Professional Photographer (PPA) From: [email protected] <[email protected]> on behalf of Michael KC1WDZ via groups.io <measter@...>
Sent: Wednesday, March 19, 2025 9:15:53 PM To: [email protected] <[email protected]> Subject: [FT-857] How can I use the 8 pin CAT connection to activate a SDR switch? ?
Looking at the diagrams I tried using pin 2 (circled in red) to activate the switch. I was under the impression it was grounded while the radio was transmitting. I checked with a DMM there is no continuity between the wire attached to pin 2 and the chassis
of the radio. Pin 3 shows continuity on the DMM.?
?
I'm using a splitter so I can run my digirig and the switch. I verified proper operation of the switch by manually grounding the wire to the power harness of the SDR switch.?
?
I also verified multiple times that the wire I'm using is pin 2.
?
?
Am I doing something wrong ? Is there a better way? The switch is looking for a momentary ground while transmitting.?
|
Mike