Astatic D-104 Rebuild & Update To Condenser Microphone

[@va3dxv]

Great video! I have so many of these in parts I might have to resurrect one like this. Clarity on the stands for anyone interested: The basic G-stand (G: Grip-to-talk) had a SPST switch and no amp, the later non-amplified stand is the UG8 (U: universal wiring/switching). The T-UG8 introduced the amplifier (T: Transistorized) newer ones with the PTT on the base were T-UP9, (T: Transistorized, U: Universal, P: Push-to-talk - but there was also a T-UG9). The 8 or 9 specified the wiring/switching (8: 4 conductor 2PDT, or 9: 6 conductor 3PDT) - There was also a GD-104 "head" which had a ceramic element rather than crystal. Merry Christmas David and thanks for all the great content!

[@ElPasoTubeAmps]

Wow... that is brilliant how the bases are labeled. Complicated enough and makes sense enough that I may be able to remember it. Thank you. Merry Christmas and a truly safe and healthy New Year. My wife and I were Mr. and Ms. Santa tonight for the make a wish foundation. It was great.

[@terrymanzel7570]

Nice video! i have a D-104 that i used with a Kenwood TS-520 with a home brew fan dipole back in the late 90's. Worked great! I made contacts all over the world with it. i recently set up an area in my house to get back in to ham radio after 20 years off the air. Still have this combination and can't wait to give it a try. Mine has the pre-amp also. Really nice to see the pieces and parts and the explanation of its inner workings. Thanks for posting!.

[@davidvogler]

Outstanding video! Great presentation and very clear for a pro or a novice. (A dummy like me!) I have multiple vintage D104 mics and this really helped me. Many thanks!

[@pomonabill220]

May you and your family have a Merry Christmas also! And stay SAFE and careful!

[@jackpijjin4088]

Yes! I needed this video. I love my D104 but the element inside disintegrated.

[@hilldwler420]

It always helps when you can monitor your transmissions . Ideally we’d all have scopes and spectrum analyzers for the fine tuning .

[@ElPasoTubeAmps]

I feel blind if I can't see my transmission on a scope. Interesting that we strive for sharp peaks to ensure fidelity but if one boosts the treble and bass like on an iCom 7300 and add in just a little compression (set at 2) it not only will have more power but the receiving end will like it better. In this case, I notice a bit of rounding (not clipping) of the tips of the oscilloscope display.

[@stephensuter7242]

Thanks - just got one of these - ready to rebuild it!

[@illusionprovideo]

Wow you did such a great job of simplifying the explanation AAA+

[@jamespeacock3036]

Thank you.

[@mikecalderon7992]

I bought one from the Whoopee Bowl out in Vinton 2 weeks ago. Nice mic.

[@ElPasoTubeAmps]

Truly a "timeless design" as the saying goes and can be repaired and put back to use in so many ways for not much money. The one I showed in the video had the battery popped and it was a bit of a mess but taking it all apart and running it thru the dishwasher was a good start to cleanup. 73

[@GroundControl204]

Great video sir, keep them coming. 73

[@Ohm10-8]

Very interesting video. I have used these Astaic Lolly Pop Style amplified microphones for 40 years. They are great microphones. However, I wired my Golden Eagle Astatic to my Tram D201A and a Glaxy Saturn I just picked up and I'm told they sound okay.. but have a 'tinty' sound. Not very good 'low end tone'. I remember back in the 80's techs used to put a resistor in place that would really bring a deep rich more full sound. I think the resistors you speak of and seeing your scope touches on the tone of these great microphones! Your thought's on ths please? Thanks, 3's

[@ElPasoTubeAmps]

I don't know anything about adding a resistor to the original crystal or ceramic microphones to give a better low-end. I can't see how that would work but they may have a method I am not familiar with. The vintage microphone elements do tend to get weaker and higher pitched with less energy in the output. I have one that still works OK and I have a friend that uses an original element and communication is good but the vast majority of the old elements are very weak and not usable. As I believe I mentioned in the video, the D-104 stands with the battery clip are perfect for a condenser mic repair/upgrade. I do not use the preamp. I have even put three microphone elements in parallel mounted in the head. Seems there is a slight improvement in it but it may just be my imagination. I guess my message here is that these old microphones are so well built and classic, it is cheap and easy to keep them running another 50 years and beyond... lastly, I will say that my ear responds to higher-pitched sounds better than bassy sounds and gets thru QRM better than low-pitched voices so I don't run the HiFi versions of microphones like some guys do and I run zero to very little speech compression and processing. Just my preference. Thanks for your comments. I hope it helps keep your magnificent D-104 microphones running for a long time. 73

[@Ohm10-8]

@@ElPasoTubeAmps very good.. and well put. I know the crystal over time does loose some of it's shine (for the lack of a better word). Personally I wouldn't want to go slapping resistors around in a good working Astatic lol. I'm looking at that M2 by Delta.. seems to be a good mic? I'm glad you posted your ebay site.. your in my favorite sellers list now. One of these days I'd like to get one of your 'puck conversions'. Others say they work well. Thanks for the reply... I learned a lot watching... 3's

[@jamesd9]

The wiring on my D104 base, is completely different than yours? Also, why are you positive and negative leads going to the same terminal?

[@kenwilliams563]

Enjoyed the video, greeting from Wales DE GW3TMH

[@EJP286CRSKW]

David, we don't care if you never get to the point ;-) Best EJP

[@jeffalessi]

Please post a link to the eBay replacement condenser element that you prefer. Thank you and have a most awesome day!

[@ElPasoTubeAmps]

I have had good luck with this one. www.ebay.com/itm/353737798123

[@jeffalessi]

@@ElPasoTubeAmps Thank you for the expeditious reply, have a most awesome weekend!

[@apexmcboob5161]

Thanks for the info; any chance you could post a link to the eBay mic you've had success with? Merry Christmas and a happy, healthy and prosperous 2022 to you and yours.

[@ElPasoTubeAmps]

I have had good luck with this one. www.ebay.com/itm/353737798123

[@joeyTR21X]

Hi question? Are you still working on D104.

[@RL-521]

Excellent work! Do you accept mail ins?

[@W4EMB]

I really love trying to fix up mics... Could you bring in the 5v from the rig to power the condenser mic? In looking at the pin out diagram, there is a 5v in the mix.

[@ElPasoTubeAmps]

I am not sure 5 volts is recommended. Mostly it seems to be 9 volts to 48 volts, depending on the microphone element. Are you sure it it 5V coming out of your radio? It may work OK with 5V, I can't say for sure.

[@Harrychess-n7y]

Gr eat video. I have d 104 about 70 yo. No bottom on base and no switch on stand. I need to update mic. How is this possible without everything it doesnt have? Harry, w3wkx

[@ElPasoTubeAmps]

I think you need another base and switch assembly that you can take parts off of to save your heirloom microphone. They are not too expensive on Ebay. I have one similar that was bought for me in 1963 when I got my general class license - 61 years old - and is special to me. I keep them going and have acquired several heads to experiment with different mic elements. I have also found that the inexpensive condenser mics sold on Ebay and Amazon have a QC problem. Some work much better than others so a simple method of evaluating them would be good. I just ordered some more... 🙂 and will work on a method to sort the good ones from the weak ones and plan on making a video. Thanks for your comments. I hope you can save your 70 yo microphone for another 100 years. 73 WA4QGA

[@arkadiuszweiss]

Welcome, I have a question why a CB radio in AM modulation is so difficult to drive, it needs very strong microphones to have a good effect, and the HAM radio is very sensitive, it is easy to control, even an ordinary dynamic microphone is enough to hear it nicely. My colleague has an old HAM tube radio, it is very modulating-sensitive, has a wide acoustic band, high dynamics of sound. Has a low coupling tendency. Old transmitters are better?

[@ElPasoTubeAmps]

The old tube transmitters do have a very high gain input circuit. Most all use a 12AX7 and as you mentioned, even low output dynamic mics can sound good. The old D-104 elements put out something like 100-200 mV and could really drive a speech amplifier to a loud volume. The electret microphones of today will put out the same voltage range so they are good like the old crystal/ceramic mics of yesteryear but they need a voltage to operate the FET amplifier built right into the little mic element. Pretty much every modern day tranceiver has that voltage for the electret microphone built right into the unit but the old units like the Collins and many others need an external voltage like a 9V battery to supply the voltage. If there are enough contacts in the mic to operate PTT plus turn the voltage on and off to the mic element during transmit and off during receive, the 9V battery will last for years. Right after making this video, I built an outboard voltage source and variable load so I do not have to have a battery in every microphone. I just change the bad element out in the mic head and plug it into the little chassis box and it supplies the 9V. Maybe a video of that would help others where the mic does not have a convenient battery holder in the bottom. Thanks for your comments.

[@arkadiuszweiss]

@@ElPasoTubeAmps Thank you very much for the explanation, Probably AM transmitters are very demanding, they need a strong modulating signal. SSB is much preferable. In my cheap CB AM, for good modulation it needs an electret microphone and at least one transistor amplifier. We used to connect it to a friend and the Amateur SSB radio was heavily loaded with modulation. CB radios like midland 77-092 are very insensitive to modulation and are difficult to control, probably have low input resistance to the microphone. These old radios like yours are wonderful. I love to look at those analog scales, nicely lit with incandescent bulbs. It is a pity that there are no such ones anymore. Health for you, the movies are great, I watch them with pleasure.

[@edgarleonayala]

i need help rewiring the astatic when the amp is removed. do you have a diagram?

[@ElPasoTubeAmps]

Here is a link to the wiring diagrams. Just search for, Astatic D104 Wiring Diagram and you should find lots of help. www.google.com/search?q=astatic+d104+wiring+diagram&sca_esv=570067020&source=hp&ei=e-gaZfLnHa-nqtsPhaePwAQ&iflsig=AO6bgOgAAAAAZRr2iwC-MPx5f3d-1u1ZOsBSumtfuRg7&oq=Astatic+wiring+diagram&gs_lp=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&sclient=gws-wiz#vhid=-c7OsS_asEqp7M&vssid=l

[@edgarleonayala]

Do you have a diagram of hoe th wires are connected on the 8 pin base? 8 -purple from potentiometer 7-shield from mike neck 6-brown 4-red from cable and other red from neck 3-black from cable and clear blue from neck 2-blue from neck 2-white from neck still need to connect dark green from neck still need to connect dark clear green from neck still need to connect brown from neck still need to connect blue from pot still need to connect orange from pot Help @@ElPasoTubeAmps

[@robertparker3580]

do you work on Turner desk mics?

[@ElPasoTubeAmps]

I have found that repairing or upgrading vintage microphones is easiest done with the inexpensive condenser microphone elements. You can get ten for $6.90 off Amazon (69 cents each...) Modern day radios with the "phantom" voltage built into the radio and supplied to the microphone, makes this easy. As for older microphones like the D-104, if it has the 9V battery holder and the preamp in the base (I remove the preamp and do not use it) the upgrade to the condenser type microphone is very easy and inexpensive also - probably $3 in parts - is the way to go and they work great and sound good on modern radios and vintage radios like the Collins S-Line vacuum tube equipment. I have a Turner desk mike that I changed to a condenser element, which I believe was originally a dynamic microphone element. The condenser mic must be turned-on and turned-off from the 9V battery with each push of the PTT switch or it will run the battery down in just a few days if left on all the time. Not all microphones have the extra contacts to so this so I have had to use very small, low current, relays in the base of the microphone along with finding a place to mount the 9V battery. Hope this helps. kzbin.info/www/bejne/kIuYe2x6aqaDqdk&lc=UgyrzivdRrQ110jjB_p4AaABAg

[@tubeDude48]

I'm guessing the CAP is a 0.1uF or 0.01uF

[@ElPasoTubeAmps]

I have tried both values even up to 10uF to see if it made any difference in frequency response and I see no difference. If it is operating in to a vintage piece of equipment like the Collins, the input Z of the radio is very high so the Xc of the capacitor is always going to be lower for audio frequencies (Xc for a 0.1 uF at 1KHZ is 1600 ohms) but for lower Z inputs like the modern day radios it might be better to use the larger values of capacitor.

[@cybertruckmax2798]

I have a D-104 Microphone for my Yaesu FT-991A. I’ve been told it doesn’t sound good at all. I was wondering if you could rebuild it for me? 73! KN4ZOO

[@ElPasoTubeAmps]

The original D-104 element was truly great for the vintage transmitters. It had a higher-pitched sound that penetrated QRM better than most HiFi sounding dynamic microphones. Unfortunately, most original D-104 microphone elements have gone bad over the decades and are no longer available new. The original D-104 is a high impedance device and works best in high-Z input equipment like the vintage transmitters. The electret condenser type microphones of today are much lower Z and work better with modern transmitters. I don't take in work projects anymore but replacing the original element in your D-104 with some of the kits available on the Internet will likely improve the sound from your Yaesu. Hope this helps. 73

[@cybertruckmax2798]

Thank you for all the advice. 73!

[@davidsharp3110]

When you replace a crystal element inside an Astatic D104 head with a condenser element, it is officially no longer a D104. It is simply a microphone masquerading inside an original Astatic microphone body. it won't even sound the same on the air. End of subject. What you have have is no longer a Made in Conneaut, Ohio D104. Look what you've done, you made a fool of everyone.

[@Just_Mike_A]

You must be a lot of fun at parties.