Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5

Shortwave Converter
#1

Has anyone had any experience with an early thirties shortwave converter? I have a Deforest Crosley model 201B that has two tubes, a 27 and a 24A. It is almost identical to the Stewart Warner 301. What I am wondering is what is the output signal supposed to be or how would one determine it. It says nothing on the schematic.

Gregb


Attached Files
.pdf Deforest 855B.pdf Size: 212.56 KB  Downloads: 208
#2

I've got the sw unit but never have used  it. I would just listen for it's output on the bcb. Don't remember if the convertor's dial is calibrated in frequency or 1-100. If it's calibrated in frequency use a generator set at the convertor's dial frequency to determine the best sensitivity by tuning the bc dial. This insures that the rf and osc are tracking properly.
Or
Bcb dial frequency= convertor's dial frequency - it's local osc frequency. So if you set the convertor dial at 2.5mc and use a well calibrated SW receiver and find the osc output at 3.5mc your bc dial setting is going to be 1mc.

When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!

Terry
#3

Usually these 2 tube units have a detector (27) and an oscillator (24) for output.

While not exactly the same, I restored one of these and tested it in a rare Northland console last month:

http://www.russoldradios.com/blog/archives/11-2016

My conclusion was that this was an interesting accessory that was not very practical for everyday use and that had been demonstrated by an early repair in which they had fixed the radio and simply unhooked the SW adaptor. But they are fun to play with.

"I just might turn into smoke, but I feel fine"
http://www.russoldradios.com/
#4

Well I have been messing around with this thing for a while now and I do seem to get some reception if the radio is tuned to 1mc and then the converter seems to work though rather poorly. I put some signals into it from my signal generator and its fairly close but does not seem to be very sensitive. I think we will call this an interesting novelty.

Gregb




Users browsing this thread: 2 Guest(s)
[-]
Recent Posts
Shadow Meter Bulb
Phorum members, I am trying to find the bulb # for PHILCO Shadow Meter part number 45-2180 that is from a 37-640 chassis...georgetownjohn — 06:53 PM
Philco 41-608 changer coupler
3D-printing...short of machining, of course. Or molding.morzh — 05:20 PM
Philco 41-608 changer coupler
Thanks, Morzh. That solves the issue of the rubber pieces. Now, I need to find a way to replicate the pot metal piec...alangard — 05:07 PM
12' Philco
If it is 12', either Kareem or Andre would have to jump pretty high to look at the front panel. Kareem would have an e...morzh — 01:48 PM
12' Philco
And here's a story about the tires on the truck. Same "no-stoop" guy must have installed these! Take care a...GarySP — 01:17 PM
Hickok AC51 tube tester
I think they have only shown the secondaries of the transformer. Two of them feed the rectifiers' filaments.morzh — 12:58 PM
IF can wire size and Rubber mounts?
Arran If the wire inside cans is the gauges you mentioned, the sole reason for that would be mechanical, to stiffen t...morzh — 12:56 PM
12' Philco
Rod, Yes, I know, but the Giant Philco is not around anymore either, so I go by whoever was alive fairly recently. H...morzh — 12:54 PM
Hickok AC51 tube tester
Absolutely no one is going to reverse engineer that circuit. Even the iron core is missing.RodB — 10:37 AM
IF can wire size and Rubber mounts?
Thanks to both members for your help regarding wire and tuner mtg supports. regards--Johngeorgetownjohn — 09:33 AM

[-]
Who's Online
There are currently 5583 online users. [Complete List]
» 4 Member(s) | 5579 Guest(s)
AvatarAvatarAvatarAvatar

>