hello everyone,I need the schematic of the receiver part
of the scr522 ,I have found one schematic on the internet but it is
almost impossible to read.Thanks very much ,73 f1gqb

I have the book on the SCR 522, but no way to scan and forward
schematics.

Do you have a specific question about the receiver? I am familiar with
the equipment. I used the BC 624 and 625 almost 45 years ago as my two
meter AM station.

John

Litzendraht wrote:
I have the book on the SCR 522, but no way to scan and forward
schematics.

Do you have a specific question about the receiver? I am familiar with
the equipment. I used the BC 624 and 625 almost 45 years ago as my two
meter AM station.

John

Hello ,thanks for your answer.I have no precise question,I have bought
one on ebay ,it is electronically complete ,and without problem (maybe
the chemical condensers to change),and mecanically the mecanism of
tuning has been removed ,but not the variable condensers and coils.
I plan to do use it to do radio-astronomy ,yes it may seem a fool
project ,but one part of my hobby besides radio-amateur is
radio-astronomy ,and I wanted to use a receiver like they were at
the beginning of radio-astronomy on vhf just to know what was received
from the sun at that time .This is why I'd like to have the schematic
with values of resistors ,condensers etc,and the
connectors ,so I can use it and repair it .
Thanks very much,best 73 alain f1gqb

nierveze wrote:
Litzendraht wrote:

I have the book on the SCR 522, but no way to scan and forward
schematics.

Do you have a specific question about the receiver? I am familiar with
the equipment. I used the BC 624 and 625 almost 45 years ago as my two
meter AM station.

John

Hello ,thanks for your answer.I have no precise question,I have bought
one on ebay ,it is electronically complete ,and without problem (maybe
the chemical condensers to change),and mecanically the mecanism of
tuning has been removed ,but not the variable condensers and coils.
I plan to do use it to do radio-astronomy ,yes it may seem a fool
project ,but one part of my hobby besides radio-amateur is
radio-astronomy ,and I wanted to use a receiver like they were at
the beginning of radio-astronomy on vhf just to know what was received
from the sun at that time .This is why I'd like to have the schematic
with values of resistors ,condensers etc,and the
connectors ,so I can use it and repair it .
Thanks very much,best 73 alain f1gqb

G'Day Alain

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.

73
Lionel L Sharp, VK4NS

nierveze wrote:


I plan to do use it to do radio-astronomy ,yes it may seem a fool
project ,but one part of my hobby besides radio-amateur is
radio-astronomy ,and I wanted to use a receiver like they were at
the beginning of radio-astronomy on vhf just to know what was received
from the sun at that time .This is why I'd like to have the schematic
with values of resistors ,condensers etc,and the
connectors ,so I can use it and repair it .
Thanks very much,best 73 alain f1gqb

Good luck with the project. I also used a 522 on 2 meters. As I recall,
they were OK in their day, but pretty insensitive by today's standards.
On the other hand, the sun is a pretty powerful transmitter! ;-)

Have you tried copying Jupiter? It's around 21 MHz; nice web site about
it. Do a web search for "Project Jove".

73,
Carter K8VT

nierveze wrote:
I plan to do use it to do radio-astronomy ,yes it may seem a fool
project ,but one part of my hobby besides radio-amateur is
radio-astronomy ,and I wanted to use a receiver like they were at
the beginning of radio-astronomy on vhf just to know what was received
from the sun at that time .This is why I'd like to have the schematic
with values of resistors ,condensers etc,and the
connectors ,so I can use it and repair it .
Thanks very much,best 73 alain f1gqb



Alain,
You might ask some of the older members of your local radio amateur
community for information and drawings of the 522. It was a very
popular set amongst hams in the post War years.

I am surprised that you will be attempting radio-astronomy work with
the BC 624. As someone mentioned, it is not a very sensitive receiver.
Most amateurs that used it began by rebuilding the front end for lower
noise and higher gain. One chap mentioned substituting 6AG5 tubes for
the 9003's. I used 6AK5's. It is a 4 channel crystal controlled unit
and perhaps for your purpose, just a few channels may be
acceptable.There are some simple changes that will allow it to be
continuously tunable from 100 to 156 Mhz without having to use quartz
crystals.

I'm sorry that I do not have ability to scan and forward information.

It might be of interest, when I was in the military, one of our search
radars operated in the "S" band (around 3000 Mhz), and I found if I
raised the antenna elevation and aimed towards the sun there was a most
dramatic increase in receiver noise.

Good luck with your project.
John

wrote:

hello everyone,I need the schematic of the receiver part
of the scr522 ,I have found one schematic on the internet but it is
almost impossible to read.Thanks very much ,73 f1gqb


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

On 2/13/06 12:56 PM, in article
, "Litzendraht"
wrote:


nierveze wrote:
I plan to do use it to do radio-astronomy ,yes it may seem a fool
project ,but one part of my hobby besides radio-amateur is
radio-astronomy ,and I wanted to use a receiver like they were at
the beginning of radio-astronomy on vhf just to know what was received
from the sun at that time .This is why I'd like to have the schematic
with values of resistors ,condensers etc,and the
connectors ,so I can use it and repair it .
Thanks very much,best 73 alain f1gqb



Alain,
You might ask some of the older members of your local radio amateur
community for information and drawings of the 522. It was a very
popular set amongst hams in the post War years.

I am surprised that you will be attempting radio-astronomy work with
the BC 624. As someone mentioned, it is not a very sensitive receiver.
Most amateurs that used it began by rebuilding the front end for lower
noise and higher gain. One chap mentioned substituting 6AG5 tubes for
the 9003's. I used 6AK5's. It is a 4 channel crystal controlled unit
and perhaps for your purpose, just a few channels may be
acceptable.There are some simple changes that will allow it to be
continuously tunable from 100 to 156 Mhz without having to use quartz
crystals.

I'm sorry that I do not have ability to scan and forward information.

It might be of interest, when I was in the military, one of our search
radars operated in the "S" band (around 3000 Mhz), and I found if I
raised the antenna elevation and aimed towards the sun there was a most
dramatic increase in receiver noise.

Good luck with your project.
John


The sun can be very helpful. At a Dew Line location where we had just
completed the Radar installations, two complete Radar equipments with
back-to-back antennas, the echo returns didn't look as we had expected, but
it was late in the day, so we gave up for the night. The next morning it
was observed that the sun was showing on the scopes, 180 degrees off.

Don

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

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