Litzendraht wrote:
wrote:

Hi Alain,

just send the schematic you need @ your email address.

Far from pefect scan in two parts, the original is large. Hope it will
help, with scissors and adhesive tape I think it can. Feddback
welcome, other request of this schematic also.

Schéma envoyé directement à votre adresse mail.... Etc!

Thierry Stora

http://www.chapelon.net




Thank you Thierry for sending the schematic to Alain. I wish Alain well
in his radio astronomy ventures with 60 year old radio equipment.

John

Hello every one ,thanks for your precious help, thanks Thierry for the
schematics well arrived at home and well printed ,time will be long now
the bc624 come from Honolulu....yesterday I went to my garage and
got the bc 625 (transmitter) I already have ,it is in nice condition.The
reason I plan to use the bc624 in radio-astronomy is simple :it is a
radio-set I found on ebay at a reasonable price (shipping included )
(before ,I had looked at hamfests in France ,and did not find receivers
in vhf old enought-1960 was the oldest),I am a long time om ,and doing
radio-astronomy on the sun since 20 years with 'good' receivers,this
project is to test with the receivers of the time of the discovery of
radio-astronomy,nostalgia ...
For those interested there is a book 'The early years of
radio-astronomy' at Cambride university press ,that describes the
material used at that time it is very interesting . In fact Reber
at the beginning around 1939 used a 31 feet parabola and a trf amplifier
with 4* 955 acorn tubes amplifier,and a 953 acorn diode ....the bc624
is of the nearly same time but as a superhet will be more sensitive ,the
9003 input tube is the successor of the 955 acorn in an another 'box'.
This is for some explanations of all the questions.
Of course if a scr522 fan club is done ,count on me with the bc625 and
bc 624.
Thanks again all of you 73 alain f1gqb

Litzendraht wrote:
Lionel Sharp wrote:

Ah memories - I used an SCR522 Rx & Tx on 2 metres way way back. They
were a great piece of gear and used by lots of hams.

Before you apply power to the receiver (or transmitter) check out the
.006mf mica HT bypass capacitors. Some of the sets used Micamold
capacitors which are dark brown in colour and are in fact paper not
mica. They used to break down with monotonous regularity.

Best to replace the lot (15 or so)in the receiver (and Tx). Some
SCR522's had good mica capacitors and if I remember they were light
brown in colour.

There were a couple of versions of the receiver that I know of. One
version had a squelch relay whilst the other version had electronic squelch.

I do have a manual but to copy the circuit it would be in 3 pieces and I
dont know how the small print would come out.Also have the wiring diagram.

There is a relative simple modification to make the RX tunable and not
crystal controled

You should be able to get a circuit locally if you hunt around, if not
let me know and will try sending you a copy.




Lionel,

Why don't we create an SCR 522 fan club? I eventually replaced the
832 PA with an 829B and ran about 70 watts, modulated with a pair of
1625's on two metres AM. Golly, those were my "wonder years". I was
still a kid in high school. I still have some 522 stuff about, but no
complete units. I do recall that all the equipment tags have the RAF
insignia.

John

G'Day John
I am sure that many of those who used the SCR522 in the past have passed
on. When I used my SCR522 on 2 metres there was no TV and consequently
no TVI. I think that TV changed all that. Even had one that was
converted to 6 metres (the TX not RX).

There was a rather large mains power supply, the RA62 produced in the
USA for the military.

The RAAF (Royal Australian Air Force) also had mains power supply made
under contract and they are heeeavy.

The RAF and RAAF designations was the TR5043.

I believe it was descended from the RAF TR1143 VHF set which was used
very successfully in the early days of WW2 for fighter control. When the
Americans saw the successful use of VHF they took a TR1143 back to the
USA and "Copied" it and produced it as the SCR522.

Only ever saw one TR1143 in a surplus shop. I think that the TR1143
would be very rare nowadays.

Someone will correct me if I am wrong about this.

73
Lionel L Sharp, VK4NS

Lionel Sharp wrote:

I believe it was descended from the RAF TR1143 VHF set which was used
very successfully in the early days of WW2 for fighter control. When the
Americans saw the successful use of VHF they took a TR1143 back to the
USA and "Copied" it and produced it as the SCR522.

You make it sound like we (the US) were doing something evil, by lending
you our manufacturing capability, and helping you with the war effort.

-Chuck

Litzendraht wrote:

Thank you Thierry for sending the schematic to Alain. I wish Alain well
in his radio astronomy ventures with 60 year old radio equipment.

I have them all the time. Can't somebody DO something about Jupiter
and the sun? They're always causing interference for me. Can't the
FCC get them shut down or something?
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

Chuck Harris wrote:
Lionel Sharp wrote:

I believe it was descended from the RAF TR1143 VHF set which was used
very successfully in the early days of WW2 for fighter control. When
the Americans saw the successful use of VHF they took a TR1143 back to
the USA and "Copied" it and produced it as the SCR522.


You make it sound like we (the US) were doing something evil, by lending
you our manufacturing capability, and helping you with the war effort.

-Chuck
G'day Chuck
No that was not the intention. Perhaps you can suggest another word that
is more to your liking
Lionel L Sharp, VK4NS

Chuck Harris wrote:
You make it sound like we (the US) were doing something evil, by lending
you our manufacturing capability, and helping you with the war effort.


Chuck,
I think it might have been more a case of "immitation is the best
form of flattery". I wasn't old enough to remember, but us Yanks were
probably using all HF radio in our fighters and bombers. But once we
got involved in the war effort, the success of the RAF and others with
VHF radio must have told us that we needed similiar equipment. We could
have certainly started from ground zero with our own designs, but
reliable aircraft communications was a vital factor at the time, and
VHF, being still a new form of transmission in those days, would have
taken months and months on the drawing boards and lab and field testing
to come up with a viable, operational unit.

I can see where it could have been quite desireable to take a known
working design, put our Yankee spin on it and get it into production.
We and the Allies had a big job ahead of us over there and time was of
essence. And yes,we were lending and loaning supplies, equipment,
manufacturing, (and fighting men as well), as a part of a team effort
to resolve a terrific world threat.

John

Litzendraht wrote:
Chuck Harris wrote:
You make it sound like we (the US) were doing something evil, by lending
you our manufacturing capability, and helping you with the war effort.


Chuck,
I think it might have been more a case of "immitation is the best
form of flattery". I wasn't old enough to remember, but us Yanks were
probably using all HF radio in our fighters and bombers. But once we
got involved in the war effort, the success of the RAF and others with
VHF radio must have told us that we needed similiar equipment. We could
have certainly started from ground zero with our own designs, but
reliable aircraft communications was a vital factor at the time, and
VHF, being still a new form of transmission in those days, would have
taken months and months on the drawing boards and lab and field testing
to come up with a viable, operational unit.

I can see where it could have been quite desireable to take a known
working design, put our Yankee spin on it and get it into production.
We and the Allies had a big job ahead of us over there and time was of
essence. And yes,we were lending and loaning supplies, equipment,
manufacturing, (and fighting men as well), as a part of a team effort
to resolve a terrific world threat.

John

Hi John,

Everything I read says the SCR-522 was a redesign of the British TR-1123,
that was done to make it possible to mass produce it with US tooling.

Certainly the US used the TR-1123 design as a quick way of getting a working
VHF design into the war as quickly as possible. It was several years before
the much more capable ARC-1 came out.

My only objection was the way the OP stated that it was copy. It had the
familiar taste of US bashing. If I read the OP's intentions incorrectly,
and it sounds like I probably did, I am sorry.

-Chuck

Chuck Harris wrote:
Litzendraht wrote:

Chuck Harris wrote:

You make it sound like we (the US) were doing something evil, by lending
you our manufacturing capability, and helping you with the war effort.



Chuck,
I think it might have been more a case of "immitation is the best
form of flattery". I wasn't old enough to remember, but us Yanks were
probably using all HF radio in our fighters and bombers. But once we
got involved in the war effort, the success of the RAF and others with
VHF radio must have told us that we needed similiar equipment. We could
have certainly started from ground zero with our own designs, but
reliable aircraft communications was a vital factor at the time, and
VHF, being still a new form of transmission in those days, would have
taken months and months on the drawing boards and lab and field testing
to come up with a viable, operational unit.

I can see where it could have been quite desireable to take a known
working design, put our Yankee spin on it and get it into production.
We and the Allies had a big job ahead of us over there and time was of
essence. And yes,we were lending and loaning supplies, equipment,
manufacturing, (and fighting men as well), as a part of a team effort
to resolve a terrific world threat.

John


Hi John,

Everything I read says the SCR-522 was a redesign of the British TR-1123,
that was done to make it possible to mass produce it with US tooling.

Certainly the US used the TR-1123 design as a quick way of getting a
working
VHF design into the war as quickly as possible. It was several years
before
the much more capable ARC-1 came out.

My only objection was the way the OP stated that it was copy. It had the
familiar taste of US bashing. If I read the OP's intentions incorrectly,
and it sounds like I probably did, I am sorry.

-Chuck
G'day Chuck.

There was no intention of US bashing or of there being something evil in
my story. John (see above) stated the situation better than I and I
agree with his sentiments.

Lionel L Sharp, VK4NS

Lionel Sharp wrote:
Chuck Harris wrote:
Litzendraht wrote:

Chuck Harris wrote:

You make it sound like we (the US) were doing something evil, by lending
you our manufacturing capability, and helping you with the war effort.



Chuck,
I think it might have been more a case of "immitation is the best
form of flattery". I wasn't old enough to remember, but us Yanks were
probably using all HF radio in our fighters and bombers. But once we
got involved in the war effort, the success of the RAF and others with
VHF radio must have told us that we needed similiar equipment. We could
have certainly started from ground zero with our own designs, but
reliable aircraft communications was a vital factor at the time, and
VHF, being still a new form of transmission in those days, would have
taken months and months on the drawing boards and lab and field testing
to come up with a viable, operational unit.

I can see where it could have been quite desireable to take a known
working design, put our Yankee spin on it and get it into production.
We and the Allies had a big job ahead of us over there and time was of
essence. And yes,we were lending and loaning supplies, equipment,
manufacturing, (and fighting men as well), as a part of a team effort
to resolve a terrific world threat.

John


Hi John,

Everything I read says the SCR-522 was a redesign of the British TR-1123,
that was done to make it possible to mass produce it with US tooling.

Certainly the US used the TR-1123 design as a quick way of getting a
working
VHF design into the war as quickly as possible. It was several years
before
the much more capable ARC-1 came out.

My only objection was the way the OP stated that it was copy. It had the
familiar taste of US bashing. If I read the OP's intentions incorrectly,
and it sounds like I probably did, I am sorry.

-Chuck
G'day Chuck.

There was no intention of US bashing or of there being something evil in
my story. John (see above) stated the situation better than I and I
agree with his sentiments.

Lionel L Sharp, VK4NS

For more details, check out www.aafradio.org - the Americans could not
communicate with t-he British who were using VHF in their aircraft, so
the SCR522 was a "copy" of the British design until the Americans could
do the necessary R & D. No slight on our American friends intended -
stop being so paranoid! - when we do want to insult you, you will be
left in no doubt hi hi

Andrew VK3BFA.

Well,
Chuck, Andrew, and Lionel,
I'm glad we got this topic resolved. And further discussion of the BC
624 and 625 can now begin.

My first two meter rig was a home brewed transceiver using a design
from the old 112mc. WERS (war emergency radio service) band. I used a
6C4 triode as a super-regen detector which reverted to an ultra audion
oscillator on transmit using a multi-section rotary switch. 6AT6 1st
audio/mic amplifier and 6V6 audio output/modulator. I had a buddy
across town that shared interest in two meters and he had a similiar
rig, but with a single 3A5 dual triode tube and it used batteries.

My rig ran on a 150 volt supply and would just light a #47 pilot lamp
as a dummy load. My friends rig on "B" batteries showed no output with
a lamp load. But it worked! We were about 3 or 4 miles apart and made a
solid QSO.

My first real two meter rig was a T23/ARC-5 transmitter that I bought
at a surplus dealer for $12. That prompted me to build a crystal
controlled converter using two 6AK5's and two 6J6's and used that ahead
of a Hammarlund HQ-129X receiver. Built a home made 5 element Yagi made
from old TV antenna hardware. I was on the air on two meter AM in fine
style.

The 522 came along a bit later when someone gave me a bunch old stuff.
I spent many hours replacing all those Micamold paper condensers in the
receiver. I had a lot of fun with the 522 and the T23 and learned a
whole lot about VHF. My present day knowledge has not advanced anything
beyond those days prior to 1960. Ha!

For you chaps down under, talking about old times motivated me to pull
an early log book. My first QSO with VK land was VK2EG on 14.065 mc. in
1957. I was running 100 watts input to a pair of push-pull 807's and a
ground plane antenna. And the HQ-129X receiver, of course.

Been a long day, I'm gonna grab a cold 807. Hi!

73, John