[Milsurplus] Pan Am radio equipment

[Michael Bittner]

OK, but the ACN, MCN and also the Types A and N (no plastic window on the 
latter two) all used the planetary friction drive referred to as "Velvet 
Vernier".  National referred to the Type B drive "Variable Ratio".  It is a 
non-planetary friction drive with variable spacing between the knob axel and 
the dial axel.  For a truly "gear shift" drive, the tuning dial on the 
AN/GRR-5 truly fits that description.  Mike W6MAB


----- Original Message ----- 
From: "Al Klase" <al at ar88.net>
To: <milsurplus at mailman.qth.net>
Sent: Tuesday, March 30, 2010 12:06 PM
Subject: Re: [Milsurplus] Pan Am radio equipment


>I think National used the "Velvet Vernier" moniker for all the dials
> that shared similar friction drive reduction arrangements. - Al.
>
>
> On 3/30/2010 2:40 PM, Michael Bittner wrote:
>> You are probably thinking of the National Types ACN and MCN.   BTW the 
>> 1940
>> Allied Radio catalog, in which I saw the National Type B dial, has an
>> artist's rendition of the Boeing 314 Atlantic Clipper on its cover.
>>
>>
>> ----- Original Message -----
>> From: "C.Whitaker"<whitaker at pa.net>
>> To:<milsurplus at mailman.qth.net>
>> Sent: Tuesday, March 30, 2010 9:21 AM
>> Subject: Re: [Milsurplus] Pan Am radio equipment
>>
>>
>>
>>> de WB2CPN
>>> Well, what was that National dial that had a 2 X 4
>>> plastic covered area above a big black knob.
>>> Freq scales or whatever could be marked on the
>>> covered area.   I thought that was a Velvet Vernier.
>>> 73  Clete