"Scott Dorsey" wrote in message
...
Henry Kolesnik wrote:
Over the years I've gone thru several 4th editions but
have never seen
any of its predecessors. I'll have to watchout for some.

I see the second and third editions at hamfests a lot.
They are often
black and less than half the width of the 4th edition so
you might not
see it unless you're looking for it.
--scott

I suspect people with the 4th edition just never sell
them. What I would love to find one day is the original
Australian edition of the 4th. The American (RCA) edition
was produced by photo-offset and some of the charts leave
something to be desired.


--
Richard Knoppow
Los Angeles
WB6KBL

Richard Knoppow wrote:
"Scott Dorsey" wrote in message
...
Henry Kolesnik wrote:
Over the years I've gone thru several 4th editions but
have never seen
any of its predecessors. I'll have to watchout for some.
I see the second and third editions at hamfests a lot.
They are often
black and less than half the width of the 4th edition so
you might not
see it unless you're looking for it.
--scott

I suspect people with the 4th edition just never sell
them. What I would love to find one day is the original
Australian edition of the 4th. The American (RCA) edition
was produced by photo-offset and some of the charts leave
something to be desired.


--
Richard Knoppow
Los Angeles
WB6KBL




Guess I'm lucky.... I have an RCA version and the one from ... well,
let's see. It says typeset in Australia and published by Billings and
Sons Ltd. London. Is that the good one?

de K3HVG



--
Posted Via Newsfeeds.com Premium Usenet Newsgroup Service
----------------------------------------------------------
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k3hvg wrote:
Richard Knoppow wrote:
"Scott Dorsey" wrote in message
...
Henry Kolesnik wrote:
Over the years I've gone thru several 4th editions but have never seen
any of its predecessors. I'll have to watchout for some.
I see the second and third editions at hamfests a lot. They are often
black and less than half the width of the 4th edition so you might not
see it unless you're looking for it.
--scott

I suspect people with the 4th edition just never sell them. What
I would love to find one day is the original Australian edition of the
4th. The American (RCA) edition was produced by photo-offset and some
of the charts leave something to be desired.


--
Richard Knoppow
Los Angeles
WB6KBL



Guess I'm lucky.... I have an RCA version and the one from ... well,
let's see. It says typeset in Australia and published by Billings and
Sons Ltd. London. Is that the good one?

de K3HVG



Nope... that wasn't correct. It says Published by Amalgamated Wireless
Valve Co. of Australia but printed and bound by the folks at Billings
(London) and dated 1954. I guess that's how they did it?



--
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----------------------------------------------------------
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The particular receiver Theo was asking about uses a 6SQ7 dual-diode, triode
as a diode detector. I found it in the 1950 Radio Amateur's Handbook.

The schematic may be a bit misleading, though, since it shows a schematic of
the diode transformer that is the same as an if transformer - which is tuned
primary and tuned secondary - with the full winding on the secondary used
for the diode. I found this concise statement in the 1942 Editors and
Engineers Radio Handbook "Diodes load the tuned circuit to which they are
connected, however, and thus reduce selectivity slightly. Special i.f.
transformers are used for the purpose of providing a low-impedance input
circuit to the diode detector."

If I were winding the i.f. transformer, I would use a hi-q secondary and tap
down for the diode, so that selectivity is maintained, while properly
matching the diode input impedance. That may be how the transformer is
connected, although it does not show that on the schematic.

Colin K7FM

"k3hvg" wrote in message
...
k3hvg wrote:
Richard Knoppow wrote:
"Scott Dorsey" wrote in message
...
Henry Kolesnik wrote:
Over the years I've gone thru several 4th editions but
have never seen
any of its predecessors. I'll have to watchout for
some.
I see the second and third editions at hamfests a lot.
They are often
black and less than half the width of the 4th edition
so you might not
see it unless you're looking for it.
--scott

I suspect people with the 4th edition just never
sell them. What I would love to find one day is the
original Australian edition of the 4th. The American
(RCA) edition was produced by photo-offset and some of
the charts leave something to be desired.


--
Richard Knoppow
Los Angeles
WB6KBL



Guess I'm lucky.... I have an RCA version and the one
from ... well, let's see. It says typeset in Australia
and published by Billings and Sons Ltd. London. Is that
the good one?

de K3HVG



Nope... that wasn't correct. It says Published by
Amalgamated Wireless Valve Co. of Australia but printed
and bound by the folks at Billings (London) and dated
1954. I guess that's how they did it?



--
Posted Via Newsfeeds.com Premium Usenet Newsgroup Service
----------------------------------------------------------
http://www.Newsfeeds.com

"k3hvg" wrote in message
...
k3hvg wrote:
Richard Knoppow wrote:
"Scott Dorsey" wrote in message
...
Henry Kolesnik wrote:
Over the years I've gone thru several 4th editions but
have never seen
any of its predecessors. I'll have to watchout for
some.
I see the second and third editions at hamfests a lot.
They are often
black and less than half the width of the 4th edition
so you might not
see it unless you're looking for it.
--scott

I suspect people with the 4th edition just never
sell them. What I would love to find one day is the
original Australian edition of the 4th. The American
(RCA) edition was produced by photo-offset and some of
the charts leave something to be desired.


--
Richard Knoppow
Los Angeles
WB6KBL



Guess I'm lucky.... I have an RCA version and the one
from ... well, let's see. It says typeset in Australia
and published by Billings and Sons Ltd. London. Is that
the good one?

de K3HVG



Nope... that wasn't correct. It says Published by
Amalgamated Wireless Valve Co. of Australia but printed
and bound by the folks at Billings (London) and dated
1954. I guess that's how they did it?

Not sure, it might be an English edition. The title
page of the RCA edition says:

Published by the Wireless Press for
The Amalgamated Wireless Valve Company PTY limited
47 York Street, Sydney, Australia 1953

Since the RCA edition was reproduced by
photo-lithography this is likely what the Australian edition
says. I take "published" to mean printed and bound. I
suspect the English edition may have been reproduced by
photo-lithograph in the same way as the USA/RCA edition was.
In both cases it would be much cheaper to print and bind
locally rather than ship complete books from Australia plus
the Ausies may not have had a large enough printing facility
at the time since the entire population of Oz was probably
not more than ten million.
The main sign of the photolighography I see is a slight
clogging of some of the charts. Not a big deal.
This was a magnum opus and I doubt if anything like it
will ever again be published in its field.
RCA, like Kodak, was an extremely good source of
educational information. For instance, the tutorial on
vacuum tubes in the front of nearly all of the receiving
tube handbooks is excellent.
We didn't appreciate this stuff when it was available.
I was given the third edition of the RDH by an engineer
I knew when in my early teens. When the forth edition was
published I bought one immediately, I still remember doing
it. It came in the proverbial plain brown wrapper which, of
course, soon got lost. Its a book you can cuddle up to and
read over an over. I learned a great deal from it. It also
has a very exensive bibliography and many of the citations
are worth looking up.
K.R.Sturley's book, also available on Pete Milette's
site, is also worth having. It concentrates on radio
receiver design but, even though both of these books were
written before solid state electronics much if both are
still applicable, for instance filter design, etc. I
strongly recomend poking around on Pete's site, there is a
lot of valuable stuff there.


--
--
Richard Knoppow
Los Angeles, CA, USA

Colin
I'm curious as to how you know what Rx Theo was asking about since I've
not seen it mentioned?

--
Thanks & 73
Hank WD5JFR
"COLIN LAMB" wrote in message
m...
The particular receiver Theo was asking about uses a 6SQ7 dual-diode,
triode as a diode detector. I found it in the 1950 Radio Amateur's
Handbook.

The schematic may be a bit misleading, though, since it shows a
schematic of the diode transformer that is the same as an if
transformer - which is tuned primary and tuned secondary - with the
full winding on the secondary used for the diode. I found this
concise statement in the 1942 Editors and Engineers Radio Handbook
"Diodes load the tuned circuit to which they are connected, however,
and thus reduce selectivity slightly. Special i.f. transformers are
used for the purpose of providing a low-impedance input circuit to the
diode detector."

If I were winding the i.f. transformer, I would use a hi-q secondary
and tap down for the diode, so that selectivity is maintained, while
properly matching the diode input impedance. That may be how the
transformer is connected, although it does not show that on the
schematic.

Colin K7FM

I cheated by asking him.

Colin K7FM

Colin
The diode load resistor in most of the diode detector circuits I'm
familiar with have several hundred kilo ohms and I think 6SQ7 diode has
a few hundred ohms so the total reflected impedance to the last IF is
the pretty much the resistive load. And if my 68 yr old memory serves
me right most commonly used IF transformers had an input and output part
number and in some cases interstage but that may have been for TV IF. I
don't recall replacing many transformers because they failed
electrically but because the little ferrite core with a hex hole would
crack and could no longer be turned. Many times this was because of a
previous repair where a monkey not a tech, tried to tweak it and broke
the core.
I also worked on a one set that had the first IF transformer installed
backwards at the IF mfg factory, not the TV assembly plant. That took
some time to find considering the test eqpt at hand was limited to a
vtvm and an audio scope.
Time to stop rambling and ask if the ARRL article distinguished the IF
transformers with different part numbers?

--
Thanks & 73
Hank WD5JFR
"COLIN LAMB" wrote in message
m...
The particular receiver Theo was asking about uses a 6SQ7 dual-diode,
triode as a diode detector. I found it in the 1950 Radio Amateur's
Handbook.

The schematic may be a bit misleading, though, since it shows a
schematic of the diode transformer that is the same as an if
transformer - which is tuned primary and tuned secondary - with the
full winding on the secondary used for the diode. I found this
concise statement in the 1942 Editors and Engineers Radio Handbook
"Diodes load the tuned circuit to which they are connected, however,
and thus reduce selectivity slightly. Special i.f. transformers are
used for the purpose of providing a low-impedance input circuit to the
diode detector."

If I were winding the i.f. transformer, I would use a hi-q secondary
and tap down for the diode, so that selectivity is maintained, while
properly matching the diode input impedance. That may be how the
transformer is connected, although it does not show that on the
schematic.

Colin K7FM

"Time to stop rambling and ask if the ARRL article distinguished the IF
transformers with different part numbers?"

Yes

The first and second stage transformers are designated "456 kc interstage if
transformer, permeability-tuned (Millen 64456)". The third if transformer
(to the diode detector) is designated "456 kc diode transformer,
permeability-tuned (Millen 65454)".

The schematic drawing for all three transformers are the same, but the
secondary of the last transformer would be different to attain a lower
impedance.

73, Colin K7FM