Wire a D104 for VOX

[Mudfoot]

Local ham wants to use his D-104 Golden Eagle on VOX, to use on his FT-950. Said he can't remember how he did it before.

Anyone know the wiring. He has the amplified mic.

 

[Dmans]

Mudfoot,
Found the info below on this link.
https://www.qsl.net/g4wpw/date.html



YAESU-FT950

PIN1 MIC UP
PIN2 + 5 VOLTS
PIN3 DOWN
PIN4 FAST SCAN
PIN5 GROUND
PIN6 PTT
PIN7 SCREEN/EARTH
PIN8 MIC

https://www.qsl.net/g4wpw/astaticbook.pdf

73
David

 

[Mudfoot]

He's want to know how to wire the base so it can be used on VOX. Supposedly, you change the internal wiring in the base.

 

[Dmans]

Changing the White wire from terminal “B” to terminal “A” (see Astatic schematic attachment)will keep the Audio line “Hot” at all times. The Yaesu will then have to engage Tx and Rx as required.

It may be possible to slide the switch lock up the hand switch to lock the Mike in transmit and get the same result??

73
David

 

[w9cll]

Rubber band?

 

[Mudfoot]

Rubber band?

He suffers from Astihophobia and won't go near one.

 

[Shockwave]

The issue here is not the white audio wire. Powering up the pre-amp without keying the TX line is the problem. Just addressing the white audio wire works on radios that don't need to use this microphones pre-amp but will provide low and tinny audio on today's radios without it. You'll need to lock the mic with the collar and disconnect the red wire through a switch. I use to run a small wire and switch right out the back of the spring to switch it for VOX when wanted. You could drill a hole if you like but I wouldn't. Remember to unlock the mic after use or you'll be replacing the battery.

Some may be tempted to use a battery eliminator but at any power level this can introduce RFI and feedback into the audio pre-amp. It can be done correctly with decent RF bypassing and filtering with an electrolytic. The 5 volt line from the radio can work but the problem is it's low enough to cause the positive peak to clip early and doesn't provide the enough bias to the transistors to remove all distortion. Another thing to consider is the microphone will lose the vast majority of its bass response as soon as you get more than a few inches away from it. Keep it close if you want good fidelity.