[ARC5] ARC-5/R-25 tuning gang question

[J Mcvey]

The original "modification" used a 75 pf mica to compensate for the missing plates on each section.This is a bit too much, to be able to tune high enough to cover the whole 160 meter band. The trimmers needed to be completely out of mesh. I changed them to 50 pf micas which alowed proper adjustment to be made at about 50% trimmer mesh.I'm just following up on the original mess to see how it would have worked. Since the dial is now  useless,  I may prefer to replace the boogered up Gang  anyway.So far the receiver still has a usable signal down to 0.1 uv in cw mode and maybe a little less!  
 

    On Friday, January 29, 2016 9:35 PM, J Mcvey via ARC5 <arc5 at mailman.qth.net> wrote:
 

 I just got into this decent R-25 specimen, which had been partially hacked under the chassis,. The Audio output transformer, 7K/10W, and the LV Choke had been removed and they have "cored out" the cable mount assembly to accommodate one of those "Ebay adaptor shafts". ( very unfortunate!) However It looks NOS, otherwise.One of the other things that was strange was that the 1st and 3rd IF cans were missing the mount screws and the hood over the gang cap was loose.
When I pulled the hood off, there were only three blades on each rotor shaft. Is this normal or was this a hack job?
I don't know if it works yet, because the RF stage is noisy/oscillating or something ( no antenna). The RF stage apears to be at least partially functional since I get a noise bump when I touch the antenna terminal. The noise goes away when I pull the grid cap. The other odd thing is that I don't hear much activity when I touch the open grid cap. 
It may just be bad caps...



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