Repairing and refurbishing the D-104 Microphone... One of the greatest microphones to sit on a desktop in front of Ham radio equipment has, for a very long time, been the Astatic D-104. This microphone, so often referred to as the "chrome lollipop" will forever be my favorite. While it was embraced by the "chicken banders" back in the early 70's, Ham radio operators have used this mic for so many years that it certainly will be enshrined in the microphone "hall of fame"...if there is such a thing. Down the ages, there have been only a few changes to the microphone but several import manufacturers have duplicated the design. If any of you remember the "Silver Salute" that was popular with CBer's and some Hams that operated AM. But less chat and more substance is really why you came here. The history of the D-104 dates as far back as far as 1933. That was the year this microphone was first produced. The Astatic Microphone Co. was originally located in Conneaut Ohio. I purchased mine, the one on the right in the picture below, in 1968. It is still one of my primary microphones in my shack.    (I replace the worn out felt on the base, you can choose any color that matches your scheme - even PINK) These Astatic D-104 microphones are all vintage. The unit on the LEFT has a preamp built in and works very well on 75 meters into my  TS-830S. The unit on the RIGHT is the TUG-8 stand with the thumb and finger paddle for PTT. The D104 in the center is one I picked up at a local CB store. This is the microphone I refurbish for this article. The two small push buttons I added for UP/DOWN memory channel control for using this one with my Kenwood TS-440SAT. So what do we need to get started ?? Well we will disassemble the base. There are 3 screws on the bottom for you to remove. Doing so will reveal the simple wiring and the wiring diagram, pasted to the plate on the inside. The microphone head has 3 pins configured to allow you to remove the head and test the wiring. It also makes it easy to change heads and/or elements if you desire. The BLACK and GREEN wires are the microphone element leads. The YELLOW and GRN/WHT leads are the PTT switch. This is the simplest base version. There is only one switch, the finger paddle on the side of the pole stand. The RED lead goes to the PTT circuit along with the braid lead. The WHITE lead is the microphone input to your transmitter. This unit is in VOX mode when the finger paddle is released. There is a clip on the base pole that allows full PTT hand free if you desire. This is the base that I will modify for an 8 wire cable that will be used with my TS-440. In the picture below you cab see the TUG-8 base with the preamplifier, battery and the level control. This unit was very CB popular for those dudes that loved to blow the tops off those old 5 watt rigs. There is quite a bit of difference between the standard D-104 and the preamp unit. As you can see this is quite a busy little base. The level control is located under a small hole that appears in all base covers for the microphone. The company did not make an all plane-jane base, or at least not one that I ever saw. The preamplifier uses a 9 volt battery, but rigs like the Kenwood's supply 8.5 volts at the microphone connector. This voltage can be wired to replace the battery. You know, the one that goes dead in the middle of the World Wide QSO party. But for now we concentrate on the base above. many of the bases were painted a cast finish with a soft grain that almost looked hammered. It is hard to see in the pictures above, but the original finish was very resilient and rarely showed scratches. The base looks like hard steel but is actually aluminum. Remove the 3 screws under the base and set the base aside. Most of these units are in good condition but the felt cover will most likely be torn around the sides and on the bottom. No big deal it is a wool felt and can be found at any fabric store, in an array of great colors. I chose red for this project. The chemicals shown above will help you restore the luster to the base. However the hammered finish will not look original. There are some hammered gray paints available but I have not found one that I like better than the CAST FINISH with a few coats of CLEAR to protect and bring out the contrast. I have used this combination on several radio cabinets. The head is simple to remove from the tower. Turning the finger nut counter clock-wise and gently lift the head off the base. The four screws on the face are #2-48 machine screws with a receiver on the rear face. There are 4 of these and they are hard to find if you lose one, so be careful. The mic element floats in the head and is held only by foam on sides and back. The sock and black sock cover simple lay under the wire screen. The face ring and rear face plate balance the element in the head assembly. These heads are easy to clean and require only a little elbow grease to keep them looking neat and shining. This one is rather ugly looking and I do not think I want to put my face up too close to the crap that you can clearly see in this picture. Imagine the sock and the sock cover ?? I don't want to use this microphone until I do this cleanup. The head parts are shown above. Note the wind sock, this material can be found at a good fabric store. The sock cover is a 50/50 fabric using cotton and polyester. Look for one in any color that you can see your hand through. This will be the sock cover. Check your element for gunk and clean if required. The side foam mounts are never a problem, it is the rear foam mount the goes bad and causes the element to rattle in the head. You can replace the rear mount with a 1/4 or 3/8 thick foam piece cut to fit the element. You will not glue this foam piece. You can polish up all the parts using Mothers Aluminum Polish. This polish will bring back the luster to all the microphone parts. Use it on the base pole and the paddles. You can replace the element for the D104 microphone. There are several companies on the Internet that offer replacement elements for this model. You can still find these on QRZ and HAM-Net for sale by Hams everywhere. They do get a little expensive on E-Gay, because of the bogus bidders, but you should be able to acquire a good one with the preamp in the base, for around 45-50 dollars US. I would not pay much more than that. I charge $25.00 to refurbish these units, and a few that I have done actually bring more than the cost at the swap meets. A few bucks in will yield a few more out. You can buy Mothers at any local automotive parts emporium. Above I show the base felt cut in "V" shape for overlap on the edge. Adding color to the base actually adds character to your D-104. I like GREEN and BLUE also, substituting the BLACK that comes with the unit stock. The contact cement UGL is the best for this application. Use a cotton swab to paint the cement onto the base plate. Be sure to sand the plate before this process, it will help retain the felt cover. Here is a picture of the base after the new felt was placed on the bottom and everything was left to set up and dry. I did not like the finish on this base and so I decided to do something about it. This is actually the same base from above. I added two small push buttons so I could use this unit with my TS-440SAT. I mentioned that the base is actually aluminum and that makes this very easy to polish. I removed all the original finish using lacquer thinner and some 400 sand-paper. When the paint was all removed I wet sanded the entire base being sure not to cut to deep. I followed that with 2 different SCOTCH polishing pads. These are also available, along with the sand paper, at any auto parts store. The SCOTCH pads will polish the aluminum to a soft luster. You can stop there if you like a flat finish, but if you want a polished finish, you can get the MOTHERS back out and polish to your content. These all polished D-104 bases were sold by Astatic in a limited edition. Yours will be a custom finished base and one that you will be proud to show off in your ham shack. The edition of a new coil cord will finish up the repair/refurbish. You can display this proudly and use it too. Probably one of the nicest accessories in the Ham Shack, and one that has withstood all the tests of time. In the picture below you can see the hammer tone finish I completed on this base. The paint is Rustoleum No. 7214, topped with 4 coats of Rustoleum Clear. It almost looks OEM. I am running this mike on my Kenwood TS-850SAT. I will be building an impedance matching preamp that will clean up the "tin" when using these HI-Z microphone elements with solid state input. I will add this update at a later date...meanwhile check out the links at the bottom of the page...some neat D104 information. Good luck with your clean-up and refurb. If you do not have the skill to complete this task, you can send the microphone to me. I will be glad to do the work for you. You can choose the base felt pad colors and decide if you want a painted base, polished base or powder coat base. I charge 25.00 plus parts (new mic cable) and shipping. It takes about 16 hours to do the job right. CHECK OUT THESE GREAT D104 MICROPHONE INTERNET LINKS... D104 MICROPHONE MODIFICATIONS and FAQ. ASTATIC HISTORY BRIEF and FINAL EDITION D104 CUSTOM and ORIGINAL MODEL D104 MICROPHONES (CHECK THIS OUT).