Hi,
Ernst Alexanderson of GE held the controlling TRF patent, on the
principle of inserting tuned circuits between successive gain stages.
It was a rather obvious concept but as just noted, everything was
patentable in those days. Interestingly, Sparton got around
Alexanderson's patent by putting all the tuning at the front end,
feeding a series of untuned RF stages.

Wikipedia is wrong. Howard Armstrong was indeed working on the
superheterodyne in 1918:

http://antiqueradios.com/superhet/

(loading is apt to be slow, since the server also handles an active
antique-radio forum).

73, Alan

Alan Douglas wrote:


Wikipedia is wrong. Howard Armstrong was indeed working on the
superheterodyne in 1918:

Wilkipedia usually is wrong. Its compiled with 'user' input. You could
submit that YOU were the inventor!

-Bill

In article ,
Bill M wrote:

| Wikipedia is wrong. Howard Armstrong was indeed working on the
| superheterodyne in 1918:
|
| Wilkipedia usually is wrong. Its compiled with 'user' input. You could
| submit that YOU were the inventor!

.... and it'll probably get reverted shortly after.

Wikipedia is usually right. Yes, it's true that anybody can edit it
-- even you! But mistakes are made, and the people who write things
aren't always experts in the subject area. Still, Wikipedia is very
impressive.

Since you know the answer, why not go over and correct the article?

--
Doug McLaren,
"Never appeal to a man's better nature. He may not have one.
Invoking his self interest give you more leverage." --Robert Heinlein

Doug McLaren wrote:
In article ,
Bill M wrote:

| Wikipedia is wrong. Howard Armstrong was indeed working on the
| superheterodyne in 1918:
|
| Wilkipedia usually is wrong. Its compiled with 'user' input. You could
| submit that YOU were the inventor!

... and it'll probably get reverted shortly after.

Wikipedia is usually right. Yes, it's true that anybody can edit it
-- even you! But mistakes are made, and the people who write things
aren't always experts in the subject area. Still, Wikipedia is very
impressive.

Since you know the answer, why not go over and correct the article?

Since you want to make a big deal out of it, I have done such a thing on
certain topics in the past only to have them "recorrected" by those with
different facts and an agenda to promote.
You can do considerably better than this source for factual information.
It can't be assumed to be any more correct than a chat room.

-Bill

In article , Alan Douglas
adouglasatgis.net writes:

Interestingly, Sparton got around
Alexanderson's patent by putting all the tuning at the front end,
feeding a series of untuned RF stages.

I restored one of those Sparton radios, and it works very well -- every bit as
selective as any other 4-stage TRF AM-BC set of the time.

I also have a spare tuned front end from that project, which I keep intending
to use as a "secret weapon" preselector ahead of a modern AM rx for BC DXing.
--Mike K.
..
Oscar loves trash, but hates Spam! Delete him to reply to me.