PTT OUT

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F4EGA
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Joined: Thu Dec 26, 2019 12:20 am

PTT OUT

Postby F4EGA » Fri Nov 13, 2020 7:04 pm

HI all,
I have been using an ANAN 200D and an ACOM 1000 amplifier for over a year without any problem, this afternoon the amplifier no longer switched to TX.
I tested the RCA PTT OUT jack on the ANAN with a continuity tester and got nothing at all when in PTT.
Do you have an idea?
I tested the amplifier with 2 others transceivers and all is working fine.
73's
Patrick
F4EGA
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: PTT OUT

Postby w-u-2-o » Fri Nov 13, 2020 8:39 pm

The proper way to measure this is to put a voltmeter in parallel with the amplifier PTT input. In RX the voltmeter should read whatever voltage the amplifier supplies as a pull up voltage. When in TX the voltmeter should read zero volts.

You can do this with any radio.

Please post the results using both the 200D and another radio.
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F4EGA
Posts: 6
Joined: Thu Dec 26, 2019 12:20 am

Re: PTT OUT

Postby F4EGA » Fri Nov 13, 2020 9:03 pm

Hi Scott,
With a TS-590 I have 12.3V in RX and 0V in TX, when I switch to the ANAN I have 3.45V in RX and the same in TX, the RCA cable disconnected from the ANAN I have 12.3V.
73
Patrick
F4EGA
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: PTT OUT

Postby w-u-2-o » Fri Nov 13, 2020 10:35 pm

Sounds like your PTT output FET is blown. Look in the schematic section of this forum, specifically for the Orion board schematic, for information on the part number you need.
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KA1GXR
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Location: ASHLAND MA

Re: PTT OUT

Postby KA1GXR » Fri Nov 13, 2020 10:55 pm

Scott:

Could there be a problem with poor ground to the PTT connector on the panel of the 200D due to the old know panel paint causing high resistance ? Mine was found that way and a good sanding and grinding of the inside of all connector and screw holes fixed that and some other connectors that tested poor to chassis ground. The bad news on that is entire back panel is pulled and all connectors get removed to do it.

Tom
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F4EGA
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Joined: Thu Dec 26, 2019 12:20 am

Re: PTT OUT

Postby F4EGA » Fri Nov 13, 2020 11:41 pm

Scott,
I ordered the 2N7002K transistor and will change it one of these days.
I don't understand how it could have been damaged!
Thanks a lot for your help.
73
Patrick
F4EGA

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