Majestic (Grigsby Grunow) 50/52 - Printable Version
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+--- Thread: Majestic (Grigsby Grunow) 50/52 (/showthread.php?tid=23853)
462ron - 462ron - 01-06-2023
Thanks MrFixr for your input but probably not going to alter this set. The next radio I come across with a power detector or grid leak I may give it a try. I don’t have any TRFs at this time except for an Atwater Kent 35 but I would need to find/build a battery eliminator and a horn speaker first so it’s on the back burner for now. My dad did tv/radio repair in the 50s and early 60s and took a NRI home study course in electronics way back when. As a teenager I started reading it and that got me hooked. I loaned it to coworker foolishly back in the 70s and never got it back! I remember reading Ron’s post on bypassing an open interstage transformer but I’ve never had to try it yet. Good stuff. When the time comes, I will have some research to do!
Ron
RE: Majestic (Grigsby Grunow) 50/52 - MrFixr55 - 01-09-2023
I hear you Ron, re not modifying the majestic other than building an adaptor that you can sub for the tube.
Re the AK 35, you don't need a horn, you can use a PM Dynamic and an output xformer from an AA5 radio. Primary impedance of about 2.5K Ohm is about right for a 01A, 112 or 71A.
You can run the AK35 or most other battery TRFs off an old computer power supply for the filaments (from the main +5 Volt Power Supply), and a bank of 9V transistor batteries for the various B+ voltages. 3 AAA cells will work fine for the bias for the 1st AF and Output tubes if using 01A or 112A as an output tube. For more power, use a 112A, 135V for the Audio B+ and -9V bias for the output stage (The 1st AF and Output stages have separate bias connections on the 35) will yield 115mW. For even more power, use a 71A. At 90V B+ you need about -17V bias (yields about 125mW). At 135V B+ you need -27V bias (gets you 375mW). The tube will take 180V B+ but you need -40V bias but you get 700mW of power
Of course If you go through about 5 sets of 9V batteries, you coulda bought an ArbeIII (I finally did).
462ron - 462ron - 01-10-2023
MrFixr that’s something to think about. The AK35 was given to me long ago and I haven’t given much thought to getting it up and running so I put it away. It’s been so long since I’ve even seen it
that I don’t remember if parts are missing. I’m pretty sure some of the tubes are. Anyway, that’s a lot of information you laid on me and food for thought! 
Ron
RE: Majestic (Grigsby Grunow) 50/52 - MrFixr55 - 01-10-2023
Sorry, Ron, TMI is what I do. (Hey, this may be my shortest post.) My last responsibility for my job is to write service procedures for laboratory automation systems. I am driving my coworkers crazy but once I retire, the info would leave with me if I don't write these documents down.
I have 2 AK35s. the only thing missing on mine are the bands and pulleys that gang the individual tuning capacitors. Otherwise, these are very simple radios. Only thing that goes bad other than the linkage is the grid leak, the interstage transformers and the wirewound resistors between the tuning caps and grids of the RF Amp tubes.
462ron - 462ron - 01-10-2023
LOL MrFixr, no such thing as TMI, it’s all good information to have. Now my curiosity is piqued as to the actual condition of my AK35!
Ron
462ron - 462ron - 05-29-2023
Well now that Spring has arrived, finally got to go out on the deck to refinish my Majestic 50. Installed new grille cloth and finished the chassis some time ago. I’m not a fan of doing cabinets so cheated a little on this one. After stripping and cleaning the original finish, the cabinet retained its original color so I didn’t see any need to use colored toner on it. I just shot it with some sanding sealer then 3 coats of clear satin lacquer.
RE: Majestic (Grigsby Grunow) 50/52 - morzh - 05-29-2023
Looks nice.
RE: Majestic (Grigsby Grunow) 50/52 - klondike98 - 05-29-2023
very nice!
RE: Majestic (Grigsby Grunow) 50/52 - MrFixr55 - 05-30-2023
Ron, a beautiful job on a beautiful, iconic radio!! Congrats!!
462ron - 462ron - 05-30-2023
Thanks guys, now onto tackling my 37-116 cabinet that I’ve put off way too long!
Ron
RE: Majestic (Grigsby Grunow) 50/52 - Eliot Ness - 06-28-2023
It looks great
If you know anyone who lives in a mobile home you can loan it to them during tornado season to keep their home from blowing away
462ron - 462ron - 06-29-2023
LOL, thanks John. When I first saw this radio at our local auction house, I liked the style of the cabinet so I bid on it and won. When I went to pick it up, I was shocked to see how insanely heavy it was for a table top radio, I think it’s over 60#. I wouldn’t have bid on it if I knew that up front. I am pleased with how it came out and it is a good performer but I won’t be moving it or rotating it much!
Ron