[TenTec] N4JK modified D-104

[Bill_Harris]

Hello Jerald:
    Thanks for putting me onto N4JK's article on the modified D-104. 

http://members.cox.net/n4jk/d104.htm 

 Are you using the Astatic cartridge on your 104?  I have an old D-104 carcass somewhere in the bowels of the shack that I wish to restore.  However, it needs a new cartridge.  Are NOS Astatic  104 cartridges, crystal or ceramic, still available?  If not, I may have to go the Radio Shack condenser mic route as per Art's other "web site" article. 


Later

Bill_Harris

 



>" Yesterday a ham friend of mine reminded me that I had some time in the 
> past mentioned seeing an article on modifying a D-104 for use on 
> lower-impendance mic input rigs... and that he wondered if I remembered 
> about the article. Well, fact is I had and that a few weeks ago I 
> actually stripped out the stock preamp in my circa 1980s D-104 and 
> installed my home-brewed version of the MPF-102 based amp detailed in:
> 
> http://members.cox.net/n4jk/d104.htm
> 
> My only modification to the circuit was the addition of a resistive 
> attenuator in the output as it was initially a bit too strong for my 
> Omni-VI Plus. In short I was more than pleased with the results with the 
> modified D-104 on my Omni-VI Plus. I had made recordings before and 
> after and there simply wasn't any similarities whatsoever. The stock 
> D-104 was tinny, thin and even somewhat distorted. The modified D-104 
> was full without being muddy and had the necessary peak around 2kHz to 
> add voice clarity.
> 
> Anyway, back to yesterday. I told my friend that I could do one better. 
> I asked him to meet me on 40 meters (he lives about 10 miles away in San 
> Francisco) and that I would demo the modified mic. Before I got to the 
> modified D-104 I began the on-the-air test with my newly installed 
> boom-mounted Heil Dual Element HM-10 (I had just used the Heil 
> microphone on the previous weekend for the SS SSB contest). My friend 
> immediately commented that my audio was really nice. I changed from the 
> HC5 to the HC4 element and he respoinded kindly. I changed microphones 
> to my Ten-Tec 700 hand mic and he said that it was nice but not 
> particulary distinguished. I then put on the modified D-104 and got a 
> rave review. In fact an easedropping ham friend of mine came on 
> frequency and echoed how great the modified D-104 sounded. Just to 
> illustrate the difference I placed a stock D-104 on and they cringed."