D104M6B some bad reports.

[GnG8d]

If you are looking for a mic that you have to shove in close to your mouth; then you just might consider getting a noise-cancelling mic instead . . .

I haven't used a hand mic in years so I'm not looking for a power mic or a n/c mic, I was just stating the obvious.

 

[Rick330man]

I little further away and turn it down

Robb's comments are spot on the mark.

I own two of these. One is wired for 5 pin DIN Realistic/Radio Shack radios. The other is wired for 4 pin Uniden. They perform very well. For reference, I have a whole collection of Turner Super Side Kicks, Turner +3 base mics, Johnson desk mics (basically a Turner +2 in a +3 body) and others to compare them against.

I never remove the modulation limiter from any radio. The resulting distortion horribly denigrates signal integrity. These mics are excellent run at about 1/2 level when speaking into them from a distance of 4" to 12". It is when you "eat the microphone" or crank the gain too high that people have problems with them.

They do tend to sound trebly, but that suits my voice fine. No clipping/snipping for my mics.

Know thy radio. Know thy mic.

 

[Ranch55]

I also played around with the tinny audio output.
I found that by clipping the 270K resistor, the bass response was very much improved.
However, if you get long winded, by clipping the resistor, it will overdrive the amplifying transistor, causing it to shutdown until the transistor cools back down.
I have experienced this very issue on no less than 6 different D104M6B microphones.
So I went back to the schematic for the original microphone. A 1.5 Mohm resistor is across the mic element contacts.
That is what I did. I replaced all the "clipped" 270K ohm resistors with a 1/4 watt, 1.5M ohm resistor.
And it has been performing very well. Bass response is greatly improved, and I have not seen any more transistor shutdown issues.
This has worked for me and all the other D104M6B mics that I have modified this way.
Hope this helps.

 

[Onelasttime]

I just purchased "ebay" a new d104m6b and waiting for it's arrival for a President HR2510 and have found a lot of negative posts on this mic. I was under the impression this was a good mic and was surprised when I Googled this mic and seen many posts about everything that could be wrong with a mic. Well I'm hoping I get a good one. How has your d104m6b been for you?

What decade was the last decade you had anything to do with 2 way radio? It has been at least 1 decade maybe 2 decades since that mic was worth owning! A lot changes in 10, 20, 30 years! Please tell me you can use a debit card to pay at the pump and are not paying your bills over a land line! TO be honest no powered microphone available for sale currently on the market geared at CB'er's is worth owning! None! If anyone tries to tell you otherwise they are probably in sales and want to sell you something! I am sure someone will point you in the direction of some RFlimited Echo Master 10,000 Super Duper Microphone as their is not much left.

If not already done do the resistor mod and recap the radio. Put a decent mic on it and call it a day. If not for use in a mobile get yourself a nice Ukrainian EQ/Compressor,Noise Gate/Audio Amp unit for it off ebay and than any mic you use will be better than a cheap power mic. If you are handy with a iron consider converting to electret condenser and sending power up the mic cord to power it! It makes an old school power mic sound like a soup can with string by comparison!

I would say the days of taking a HR2510 and slapping a Minute Man Estatic Mic on it are long gone as in 1990's gone! One of my friends in the Army went by Ruber Chicken at Ft. Stewart and he had that setup. Not sure if it was HR2510 or President Lincoln but it had the MRF477 final and a Minute Man D104M6B and that was a nice setup! Almost as mice as my Lincoln with MRF455 final.

Take care of your HR2510 they do not build them like they used too especialy if you are into SSB!

 

[Low_Boy]

It will not be a good one. Switches stick and make a clank sound. They are a loud microphone. Should have did som research before buying.

 

[Shockwave]

The switch is the weak link. It becomes noisy over time. Oddly enough, typical contact cleaner does not work as well or last as long as the WD-40 trick.

 

[Ranch55]

Yes, the switches are the weak link, I agree .......
Some time back I was able to procure some higher quality switches for these microphones.
I have changed out several and also added a jumper wire across two of the pins which has improved the performance of the switch.

 

[hotrod]

unfourtanly in 2019 theres not a whole lotta mobile power micsd out there anymore to choose from brand new.. now if ya would,ve went looking for used mic i recommend a astaic 575 or a handheld tuner [cant remember mode numer] but its a plus 2 handheld ..there nice too. or find a d104m6b or c made by astatic

 

[Van Lifeson]

Where is the 270k resistor? I don’t seem to have that value in my d104m6b.

 

[2NC995]

It's marked on the board.

It's right at the end of the connector where the cable attached to the header pins.

Http://worldwideDX.com/threads/d104m6-vs-d104m6.252415/page-2#post-708216

 

[Slowmover]

Got six of them. People don't know how to use them right, get frustrated and give them away. Get xlnt reports with mine - all of the time. They don't listen to me, they give me their mic because they doubt what I said, and then I do a mod to it and set it right and then they are amazed. Laugh every time.

The first 'trick' is to not let it over-modulate; which is what 90% of people end up doing. Very common mistake. Set the mic gain on the mic to 1/2 the way up, and not one ounce more. No matter what. Yes; you can do a little less (1/3 open); but not more than 1/2. Next, turn the mic gain on the radio between the twelve o'clock to one-thirty position; and not an ounce more. Talk 1 ft away in a normal voice; as this will also makes a huge difference.

The next trick is to put the AM Limiter back in the radio if it had been taken out. That mod almost always works lousy, because people turn up the gain on their mic and radio until the radio is into full distortion. Stupid. Waste of time/resources to remove the limiter, regardless of what make/model it is. Then they wonder why the mic sounds like crap. Small wonder; eh?

The last trick is to clip the top of the 270k resistor lead in the mic. Just one little >snick<. It is right next to the mic cable plug on the mic board. This particular resistor has a red-violet-yellow-gold bands on it; in that order. This will widen up the freq response of the mic (more bass and better highs; not muddy or tinny sounding in the least bit). The resistor will limit the audio response if it is left in mic's circuit; the stock mic sounds 'tinny'. You don't have to remove it at all; just clip the resistor lead on top or the side, as this resistor is mounted vertically on the board. In case you don't like it, all you have to do is solder the clipped joint. But rest assured, if you have done everything correctly above, it will sound nearly as nice as a wide-banded Silver Eagle - if not better. Most people think that is what I use, and then I explain it briefly to them and they are surprised.

Nice mic; nice choice . . .

I’ll try those settings (mobile with DX-959).
Thx.

.

 

[Slowmover]

mine was in the mobile so I would run mine with the mic between 2 and 3 with the radio mic gain wide open to minimize wind noise.
like Robb says, don't over do it and you should have a good sounding microphone.

That’s the way I’ve been running mine (mobile) and may return to it.

 

[Slowmover]

I also played around with the tinny audio output.
I found that by clipping the 270K resistor, the bass response was very much improved.
However, if you get long winded, by clipping the resistor, it will overdrive the amplifying transistor, causing it to shutdown until the transistor cools back down.
I have experienced this very issue on no less than 6 different D104M6B microphones.
So I went back to the schematic for the original microphone. A 1.5 Mohm resistor is across the mic element contacts.
That is what I did. I replaced all the "clipped" 270K ohm resistors with a 1/4 watt, 1.5M ohm resistor.
And it has been performing very well. Bass response is greatly improved, and I have not seen any more transistor shutdown issues.
This has worked for me and all the other D104M6B mics that I have modified this way.
Hope this helps.

That sounds like a worthy approach. Thx.

.

 

[Holydvr]

I did the same inadvertently with a pc122. Someone had turned the amc up pretty heavily as far as modulation goes. I did not know this. Even an sra-198 would make it sound like garbage due to over modulation. But, I could run the M6B just cracked open and sound like the bees knees, with no other noises interfering. I kind of wish I had not screwed that screwed up setting up..