[ARC5] BC-186 query

[John McCarty]

Hello Roy and All;

    I've tinkered with one of these receivers. It's basically a "three 
stage blooper" from the 30's. I haven't pulled the
coils from mine but given what the base is like it shouldn't be too 
tough to wind some new ones. I
would try to wind my own before I cannibalize another set. ARRL 
handbooks from the 30's would
give you direction on how the coils should be wound.

   Having said that, as far as putting it on the air, this set would 
have the same characteristics of the 3 stage regens.
It was designed to work with a short fish pole antenna. so the RF stage 
runs wide open. This leads to blocking with
stronger signals on a full sized antenna. Closing switch S2 which shorts 
out the input helps sometimes. Since I only have
the rx and transmitter, and I'm running off a home brew battery pack, I 
was thinking of a pot that would allow higher bias
voltage to the grid of the RF stage and allow for some gain adjustment, 
externally from the set. Don't know how the
change in gain on the RF stage would impact the detector.


Years ago I had the battery box and gave it away thinking "What am I 
ever going to do with this???"



  ARC-5 content: These sets were listed for air-to-ground comms.


73


John n9hrt



On 3/4/2012 12:26 AM, Roy Morgan wrote:
> Radio folks,
>
> I've been asked my opinion about a BC-186 radio.  The fellow has a
> transmitter and a receiver with no tuning unit.  There's a receiver on
> eBay just now.  I know next to nothing about these sets.  Does anyone
> have experience with them?
>
> Roy
> Here's part of his email to me, and a link to a fellow who has used a
> set:
>
> 	From: 	unimat9317 at hotmail.com
> 	Subject: 	Question about BC-186
>
>        I have a Signal Corps BC-186, ... I have the matching
> transmitter and battery box for it, with matching serial numbers,
> but ... The receiver is missing the tuning unit.  The tuning unit is
> shown in this eBay listing of what appears to be a complete unit:
>
> <http://www.ebay.com/itm/140712141188?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2648
>   >
>
>        I've got a few questions. First, is it worth attempting to get
> my pair working again and back on the air? Is it better to just buy
> the one on eBay? If I did buy the ebay one, would it be worth my while
> to remove the tuning unit and put it into mine for the sake of a
> matching numbers set, or should I build something from scratch to put
> into mine?  ...
> Thank you,
> Seth Gottlieb
> KB3LLV
>
>
>
> Link:
>
> SCR-178
> people.csail.mit.edu/sw/html/NS1W/scr-178.html
> The equipment includes the BC-186 receiver, BC-187 transmitter, and
> BC-188 modulator.
> I had a BC-186 receiver as a kid that I used for some attempted QRP ..
>
>
>
>
>
>
> Roy Morgan
> k1lky at earthlink.net
> K1LKY Since 1958 - Keep 'em Glowing!
>
>
>
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