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Ok, Terry, I rewired the power supply to match the schematic.. Now I have different problems..
Here is what power supply looks like now..
[Image: http://i292.photobucket.com/albums/mm38/...dzzlkb.jpg]
I measured the following..
B+ Red Lead to GND +45 Volts DC
B+ Red Lead to GRN lead B- +323 Volts DC
Brn lead to GND 13.00 Volts AC
Then measured the Grn B- to Gnd -274 Volts...
The TX schematic says B+ should be +200 Volts But doesn't say B+ to what GND?? or the GRN B- lead..
[Image: http://i292.photobucket.com/albums/mm38/...itrqty.jpg]
Here is what I did. Replaced C206,C207 and C209 with exact values .. Added C208 per schematic..
NO hum now but RX audio Very low..
What am I doing wrong? Should I rewire like it was before?
Help Skip..
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Try disconnecting C-208. Having -275v across it tells me that there is no load connect to it (somewhere in that mess of a schematic there might be an open low value resistor across B- to chassis gnd. It's not in the p/s chassis) or it's not suppose to be there. Nothing in there needs that much - voltage. There is two different P/S diagrams right? One w/ 208 and one w/o.
Typically measurement are from chassis ground.
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
(This post was last modified: 04-15-2017, 06:18 PM by Radioroslyn.)
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
No there isn't 2 Diagrams.. My power supply was wired without C208 and had that coil Cap and Diode added .. The hand drawn drawing I made .. The other is the schematic that I found online for the Communicator lll.
Skip...
(This post was last modified: 04-15-2017, 08:08 PM by vecher.)
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
PS I just removed C208.. Then I get NO B+ voltage at all to Ground..
Skip...
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Hows come ur power plug has 5 pins and the one on the schematic has 6??
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
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Good Question.. No Clue.. The power plug from the power supply and the one on TX that it adapts to look original as far as I can tell. Maybe there is another set of schematics out there.. Not sure..
I will take a couple of more pictures of both connectors..
Skip...
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Ok put c208 back. Measure the resistance from RFC 4 at the power plug to ground. Should see abt 500 ohms.
Looks like R13 your adjustment for the meter. You didn't mention what position the meter sw was in when it was pegged? This only adj in the rx position.
Also look at the p/s chassis and see if there is a 4 digit number starting w/3
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
(This post was last modified: 04-15-2017, 09:20 PM by Radioroslyn.)
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Ok, Terry.. Here is what I found out..
1. No numbers on the power supply .. except 305 in a circle..
[Image: http://i292.photobucket.com/albums/mm38/...sysn76.jpg]
2. Tx has number of E-2654
3. RX has number 3147
I have NO RFC4 .. That point goes directly to the coil of a Relay .. I measured about 14.4 K
[Image: http://i292.photobucket.com/albums/mm38/...m81elv.jpg]
I have this resistor used in first run only...
[Image: http://i292.photobucket.com/albums/mm38/...wo2pmi.jpg]
So looks like I do not have the right schematics for this set..
Skip...
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
>1. No numbers on the power supply .. except 305 in a circle..
Was hoping that it had a model # for that power supply.
>I have NO RFC4 .. That point goes directly to the coil of a Relay .. I measured about 14.4 K
I suspect that's why you got so much negative voltage. That negative voltage is used to grid
block key an external VFO. The rca jack on the back marked vfo is not the signal it's for keying.
Also it goes up to the mic jack so may have some sort of ptt circuit.
>So looks like I do not have the right schematics for this set..
Or maybe it has the wrong p/s. Don't know.
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
(This post was last modified: 04-15-2017, 10:36 PM by Radioroslyn.)
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Ok, well since I do not have the right schematics to match .. I am going to put power supply back to the way it was when I received it.. I did document the way it was..At lease it worked then with good volume and TX..
Had a load HUM however.. And I think the B+ was way high.. Will see after I get it back to the way I found it wired..
Then Go from there.. Unless there is a different approach I should use...
Skip..
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Sounds like a good plan. I'd rather get rid of hum than try to redesign that p/s. I'm curious about the bias circuit from what I can tell it doesn't look like it needs it with the exception of an accessory vfo and maybe to operate the 2 relays.
Hope I don't become expert on these things!
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
Posts: 7,294
Threads: 268
Joined: Dec 2009
City: Roslyn Pa
Don't know if you saw this in your endeavors to work on your goonie but thought it was a pretty fun read.
http://www.eham.net/ehamforum/smf/index....986.0.html
I looked other communicator manuals but didn't is any thing like your supply. Older ones had tube rectifiers and newer ones had silicon bridge rectifiers.
You gotta 8.4mc rock?? That will put you on the 6mtr AM call freq.
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
(This post was last modified: 04-16-2017, 12:03 PM by Radioroslyn.)
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
No havent seen it.. This was given to me by a friend when we went out to Lancaster to get a duplexer from him for our AF MARS repeater..
It came with the following Frequencies
50.100
50.148
50.190
50.238
51.000
Skip...
Posts: 933
Threads: 140
Joined: Mar 2015
City: Lansdale
State, Province, Country: PA
Ok, Rewired power supply back to the way it was when Received..
I now get..
B+ to GND 332 Volts No load..
B- to Ground -56 Volts to Ground..
Skip...
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