[Boatanchors] FW: HRO-60 Mystery Plug-in Chassis

[Richard Knoppow]

----- Original Message ----- 
From: "D C *Mac* Macdonald" <k2gkk at hotmail.com>
To: <boatanchors at mailman.qth.net>
Sent: Sunday, February 27, 2011 1:26 PM
Subject: [Boatanchors] FW: HRO-60 Mystery Plug-in Chassis


>
> One of the HRO-60s I have acquired came with a plug-in
> chassis that has a transformer, three tubes (6BY6, 6Bc7,
> and 12AU7) plus a potentiometer on the top side.
>
> Does anybody have any ideas what this might be?
>
     Three possibilities:
1, crystal calibrator
2, NBFM adaptor
3, product detector

The first two were offered as accessory items by National 
and I am pretty sure there are schmematics on BAMA that 
would also identify the unit. There were a number of product 
detector mods published at least one of which was made to 
plug into the NBFM socket. I have not done a search for 
this. I think the HRO-60 has separate sockets for the 
calibrator and NBFM with switches on the front for each. See 
if one or both work.


--
Richard Knoppow
Los Angeles
WB6KBL
dickburk at ix.netcom.com