[HBR] more pictures

[hbr@mailman.qth.net]

In a message dated 5/11/02 10:14:47 PM Eastern Daylight Time, 
windy10605@juno.com writes:

> Pictures of Darrell's  21 tube, triple conversion, receiver have
>  been uploaded to the web site. 

Nice piece of work! 

> If anyone recognizes the 
>  receiver and where/when/if it was published, we'd all like 
>  to know. 

This much I know: It was never in QST or the ARRL Handbook.
The last IF looks to be very similar to the DCS-500, using "width coils"
at 50 kHz.  

>Heck of a receiver for it's apparent age (octal tubes).

It could be much newer than the tube types would indicate. The Eddystone
dial appeared in the late 1950s or so, long after miniatures were all over the
place. The bakelite in the Miller coils, and their label style, indicates 
they are
relatively "new" (if one can say a quarter century plus is "new"). The chassis
arrangement, internal power supply and front panel layout appear to be 
HBR-16 inspired. There may also be a bit of HB-65/67 influence.

Looks like the Unknown Builder combined lots of good ideas into a masterpiece.
As for the use of metal tubes, the Builder probably had big piles of them, 
with 
good sockets to match. No headaches with shields, and for many uses there is
no performance advantage to miniatures. For example, for AF output use,
a 6AQ5 is just a mini-6V6 that can't be pushed quite so hard. 

I am old enough to remember when all of the parts to build such a project 
could
be picked up at a hamfest for relatively few dollars, because things like B&W
TV width coils, 6K8s and even 898 dials were considered "junk". The Builder 
may have taken advantage of this.

My best guess is that the RX was built in the late 1960s or early 1970s.

Some questions:

- How well does it work?
- What's the mixing scheme (IF frequencies, etc.)?
- Schematic, block diagram, other info?

Thanks for the photos and info. Warms the ol' ticker to know such things 
exist.

73 de Jim, N2EY