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Red_devil
Junior Member
Username: Red_devil

Post Number: 47
Registered: 10-2004


Posted on Tuesday, February 15, 2005 - 7:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Techs or other CEF members

Any Ideas on this would be greatly appreciated. I am trying to rewire a Turner +2/U microphone made in West Germany for my Uniden PC 244.

PIN #1 ~ SHIELD / GROUND
PIN #2 ~ WHITE / AUDIO
PIN #3 ~ BLACK / TRANSMIT
PIN #4 ~ RED / RECEIVE

I have included below an excerpt from the Turner wiring manual. If you can not read the image, I can e-mail you the entire manual in .pdf format.

I know that the JM+2/U was originally designed as the electronic switching radios and the M+2/U was for relay type radios. This microphone was originally used on an old Sears Digital-40 radio. Maybe it canít be used on a newer radio :--(. I have rewired the microphone internally like the diagram shows and also double-checked all connections. However, the audio is VERY low and it squeals when I turn it up to about 5.

On the old radio it had very nice audio.

IDEAS ?????

CEF447
Red Devil - 392
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Red_devil
Junior Member
Username: Red_devil

Post Number: 48
Registered: 10-2004


Posted on Thursday, February 17, 2005 - 4:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Are there ANY Mic. guru's out there? I know it is not as simple as the right color wire to the right pin but, you haven't failed me yet.

CEF447
Red Devil - 392
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Racer_x
New member
Username: Racer_x

Post Number: 3
Registered: 2-2005
Posted on Thursday, February 17, 2005 - 10:16 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

How does a stock microphone work on the radio? Is the audio level about the same or better than the Turner?

The squeal sounds like too high of a level from the microphone causing the radio's audio circuit to go into oscillation. Does the squeal go away when you turn down the mic gain on the radio?

This may sound pretty basic, but have you tried a new battery?
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Red_devil
Junior Member
Username: Red_devil

Post Number: 49
Registered: 10-2004


Posted on Friday, February 18, 2005 - 1:21 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Racer X,

Thank you for responding. My stock mic works well but I need to almost eat it for descent modulation levels. My D104-M6B works VERY well. This turner has been in a box for about ten years. It has a new Panasonic HM-5C battery. WOW, those are a bit hard to come by these days. I guess thatís what you get when you try to use an antique :-).

As for the mic gain, Iíve tried it. Iíve also roatated the power dial quite a bit thinking that storage corrosion may have been part of the problem. I may tear it apart later for a closer look but, the squeal is appearing much less after working the dial. However, the audio is only at about 20% mod.

Thanks again!!! Any Ideas will help.

CEF447
Red Devil - 392
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Racer_x
New member
Username: Racer_x

Post Number: 8
Registered: 2-2005
Posted on Saturday, February 19, 2005 - 8:33 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I've got a friend with an M+3 and it sounds fantastic on his Uniden PC122. I wish Turner still made microphones for CB and Ham because they made great stuff.

Well, if the stock mic and the D104M6B work on the radio it's not the radio. And with a new battery it's not that.

I've got some more questions for you:

Does the audio sound good even though it's at such a low level?

Did the microphone ever have a leaking battery in it?

Are the battery contacts nice and shiny?

Are the solder joints nice and shiny?

Have you tested the wires with a meter from the switch to the micrphone plug to see if there is any resistance or maybe a broken wire?
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Red_devil
Member
Username: Red_devil

Post Number: 53
Registered: 10-2004


Posted on Saturday, February 19, 2005 - 2:24 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Racer X,

It sounds OK, as best I can tell even though the audio is low. If I drag my fingernail over the mic screen it sounds good (Hmmmmmm).
I did rotate the insulating paper and foil away from the circuit card and it does appear that it had a battery leak in it once (not while I owned it). I see no other corrosion in the microphone. The only deterioration seems to be with the insulating paper I have repaired the damaged paper with electrical tape.
The battery contacts are nice and shiny. I have checked continuity along the foil which surrounds the circuit board and mic element. The foil is all Ė7v like I assume it should be.
There is good continuity from the plug through the mic cord and to the PTT switch.

Thanks for the help with this :--).

If you want photos I can e-mail you any nice close ups that you may need. Drip me a line at the e-mail address on my CEF Profile.

CEF447
Red Devil - 392
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Racer_x
Junior Member
Username: Racer_x

Post Number: 11
Registered: 2-2005
Posted on Saturday, February 19, 2005 - 7:19 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

You said the foil is minus seven volts? It would guess it should be 0 because it's normally used as a shield to protect from RF. Check the continuity between the negative battery terminal and the foil. Is the battery in backwards?
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Red_devil
Member
Username: Red_devil

Post Number: 54
Registered: 10-2004


Posted on Saturday, February 19, 2005 - 9:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Racer X,

Maybe a poor choice of words on my part. It has negative continuity. The foil has continuity with the negative battery terminal and all other grounded materials in the microphone. When put the positive side of my miltimeter to the positive terminal, then the negative side of the meter to the foil shield I get 7v. Just like the shield wire pin #1, the PTT Switch housing etc.

I have included a photo this time to help a bit. The positive battery terminal is on the left as you see in the photo. This explains the area around the terminal where the foil is pulled away by design. The previous owner also idiot proofed it by marking a + into the foil.

Thanks for asking and trying to help me! More photos also available.

CEF447
Red Devil - 392

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Racer_x
Junior Member
Username: Racer_x

Post Number: 15
Registered: 2-2005
Posted on Saturday, February 19, 2005 - 10:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Okay I understand what you meant now - sorry for the confusion. I don't know what else could be going on here except that there is a component that has gone bad or perhaps the element has a problem.

It's a dynamic element isn't it? If the impedance of the element is low - below 1000 ohms - perhaps you could temporarily connect the element directly to the radio to see what kind of audio output it has on it's own. If it's still pretty good then you can guess the amplifier is to blame, and if it's not you can guess it's the element.
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Red_devil
Member
Username: Red_devil

Post Number: 56
Registered: 10-2004


Posted on Sunday, February 20, 2005 - 10:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Racer X,

Thank you for all of the help. Dynamic element impedance measurement is beyond my level of technical expertise. I am studying more on electronics and may be able to do this soon. Otherwise, there are several shops in the area. I may just pay someone else.

Thanx again for trying!!!!!!!!

CEF447
Red Devil - 392
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Red_devil
Member
Username: Red_devil

Post Number: 57
Registered: 10-2004


Posted on Monday, February 21, 2005 - 9:24 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Racer X and other readers,

You wonít believe this I was wondering why some sounds were better picked up by the microphone i.e. fingernail on the screen while other less harsh sounds (voice) were not picked up as well. LOGIC SET IN... upon a closer inspection of the microphone, I saw that the cone had become detached from the small pin in the center. No movement, no audio right? A tiny dab of epoxy to connect the pin to the cone and the old Turner was up and running.

The squeal issue seems to have resolved itself. I guess as stated above it was due to minor corrosion on the adjusting knob maxing out the audio.

Thank you for trying to help.
I hope this posting may help someone in the future

I'm becoming addicted to these silly little smiley things. Let me know if I go too far?



CEF447
Red Devil - 392
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Racer_x
Junior Member
Username: Racer_x

Post Number: 38
Registered: 2-2005
Posted on Friday, February 25, 2005 - 8:37 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Cool deal. I'm glad it's working for you Red devil.

BTW - I read the explanation of your handle and it made me laugh. I'm a redhead too. I don't know if I should blame my German heritage or my red hair for my poor temper, but it still gets the best of me from time to time. I just got a new security badge photo taken for work, and I was told I resemble Satan in the photo because if my bright red Vandyke.

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