hy-range IV Base No Transmit

[Gashog]

Anyone care to help me diag my new 23 channel base station?
I have soldered in a "new" speaker and a 1k ohm resistor + LED behind the meter.
All after cleaning the mold from inside the case and off the PCB with $8 worth of CRC.
It receives but transmits only a 60hz hum and no voice.

I did notice one crispy looking component.
Some sort of coil the size of a 2 watt resistor.

 

[midnight special]

if it is the one with the nine pin socket on back is the jumper in place? usually the only high gain IV with the socket has a 4 pin mike plug,,,, the 5 pin din doesnt have the socket on back,,,,,,

 

[Gashog]

if it is the one with the nine pin socket on back is the jumper in place? usually the only high gain IV with the socket has a 4 pin mike plug,,,, the 5 pin din doesnt have the socket on back,,,,,,

Yes it has the plug in back.
I'm using a 4 pin mic that I have tested on my mobile.
The jumper is in place but I will check to make sure i is making good connection.

Are you familiar with the PCB layout?
The component mentioned above had gotten hot enough to stain the metal heat sink or bracket next to it.

 

[Robb]

What is the model #?
673 or 673B?
http://www.cbtricks.com/radios/hygain/index.htm

 

[midnight special]

service manual.....


http://www.cbtricks.com/radios/hygain/hygain_673/graphics/hygain_673_pr_sm.pdf

i dont remember right off but the mike wireing i dont think is standard cobra,,, the site above will have the mike wiring in it,,,,, you are lucky with that radio it is rare,,, if you get it going be on look out for the vfo that matches it,,, i am lucky to have one in my hygain collection,,, i am looking for the hygain V with the vfo socket on the back,,,,

 

[midnight special]

after looking in my hygain service books and notes,,,,,
if you are trying to use a cobra style mike it wont work,,,, cobra is wired


1 audio grd
2audio
3ptt
4rec,


hygain is

1 audio
2grd
2common
3ptt
4 no connection...

this might be why you are having the hum and such,,,,

oh and to add you dont have to have the mike plugged up for it to recieve

 

[Gashog]

It's a model 673.
I have an old Motorola mobile mic with male plug.
Would it be OK to solder a female plug onto it, or would that be ruining a valuable mic that deserves better?
Looks like this one, but with a red M.

Also....Fascinating about the VFO.
What a cool feature!
I'll be on the lookout.

Edit: I noticed it's rated at 5 watts?

 

[Robb]

Motorola mics weren't built for CB radios. The circuitry in there is designed for their companion radio. Not going to have the desired end that you seek with it, I'm afraid . . .

 

[midnight special]

yep the vfo is neat makes it recieve 40 + channels,,, but with just a wire cut it will transmit thru vfo...... that is why i am looking for the hygain V with vfo socket on back,,,,,

 

[Gashog]

What are my mic options?
Rewire the one from my recently deceased Uniden?

Does the VFO for my hy-range have to be a IV or will others work?

 

[midnight special]

rewire from a uniden will work,, mine has a d104 with a tug 8 stand on it,,,,

http://www.cbgazette.com/hygain-674-675-2_cw.jpg


picture of vfo with hygain V,,,,,, the vfo was made to fit several models,, but fcc made hygain stop because to transmit you only had to cut one wire in side to transmit from below channel 1 up past channel 40

 

[Gashog]

So you have a VFO VI on a hy gain V.
I'll keep my eyes open for one for mine.
I've not seen even a picture of a VFO IV.

The guy I picked up the box o cbs from has found a box o mics.
He's sending it to work with his wife for me.
Hopefully the original hy gain is in there.

 

[midnight special]

the vfo is called hygain 675a,,, it comes up every once and a while on ebay,,,,

the vfo i have is on my hygain IV,, i am looking for a hygain V someday hoping to find one

 

[Gashog]

the vfo is called hygain 675a,,, it comes up every once and a while on ebay,,,,

the vfo i have is on my hygain IV,, i am looking for a hygain V someday hoping to find one

If I find one, I'll swap with you

 

[Gashog]

I rewired a mic and got it to transmit.
The audio is very faint but the hum is still loud.
Also, I noticed the lights in the radio going dim when keying the mic.
I replaced the coil with a similar one scavenged from a broken radio.
Same symptoms.

The new coil (as close to the original as I could find) will look like the one I took out if I key the mic a few more times.
It gets hot quick!
Something on the other side of it is shorted. Should I be looking at caps?