Post war 120volts to 12/24 power supply.

[Bob Carriere]

I started my Winter project with the 19 set by first making sure the power supplies would at least work.

Well the first one did.... the outside is dented, splattered with paint drippings but works like a charm.

The second one, the clean one with the canvass cover, is dead as a door knob. Preliminary testing "seems" to indicate a faulty main power switch......if that is all it needs I will be lucky.

But before I dive any deeper...... the two power supplys are of different construction.... outside is the same but the guts are slightly different.

Now for my questions....

Are there any wiring diagrams/schematics.....or manuals available to guide me along this route..... there maybe more than one model....

Thanks for your help.

Bob C.

[Mike Kelly]

Hi

There are different power supplies . The Mk 2 sets had a large single rotary transformer that ran both the transmitter and receiver , this was not a efficient method as it drained the battery .

To save battery power, the Mk 3 power supply had two smaller separate rotary transformers , one above the other . In receive mode only , the smaller transformer was on .

In the case of the Canadian Mk3 they used a vibrator unit to power the receiver on the set .

I guess you know of the 19 set web site ?

Mike

[Bruce MacMillan]

Bob, can you post a photo. There was no 120v to 12/24v power supply for the 19 set per se.

Are you talking about the CPP-2 made for the C42 & other Larkspur stuff? Big green box, VERY heavy.

[Edwin Wand]

In the 1950's we used a 120v power supply/converter for the 19 sets in Canada. Cant remember the model no or manufacturer but as noted it was very heavy. Mounted on a wooden base it took one man on each side to carry it. Others with direct RC Sigs experience could probably help out with more detail. Ours were painted OD and were about 18 "x12"x12". In the field we used 2 six volt and later 1 12v batteries.
Our 19 sets were replaced by the 510 and 26 set about the mid 50's, with the exhausted 26 set batteries being used to power razors

[Bob Carriere]

Sorry for being unclear I am talking about the CCP - 2 power sypply with a knife switch to give 12 or 24 volts.....actually more like 14.6v and 28.7 v.

The other 110 v power supply for the 19 set that fits on the board will be examined later...

Will post pictures later today....... both date stamped 1952.

Will attempt to cannibalize a double pole single throw switch from an old NRC research panel of the late 50s.... the original switch has screwed on terminals while the salvaged switch had soldered terminal..... trying to keep it original as possible...... and screwed in terminals are so much easier to service later.

Mike...... can you post the 19 set site.... thanks.


Bob C

[Mike Kelly]

Originally Posted by Bob Carriere

Mike...... can you post the 19 set site.... thanks.


Bob C

sure

http://www.qsl.net/ve3bdb/

[Bob Carriere]

EUREKA........Got the CPP 2 working.

So simple yet......

I hunted down a separate used double pole single throw switch from a surplus NRC panel. Tested fine..... ready to be used as a substitute.

Removed the original switch from the CPP 2 and tested again.....seemed to work on one pole....... so being fearless and being that this is pre solid state.... the switch is actually assembled with two screws sealed with some black dry brittle paint. Decided to take the switch apart to see what was defective or broken.... chipped the paint and carefully took it apart laying out the small pieces.... contacts were a bit black and oily...... washed everything in an electrical contact solvent.... bent the contact arm for a bit more pressure and re-assembled...... now works perfectly.

Output dial works and puts out 13.4 to 19 volts in the low range and 26 to
39 volts in the upper range.

Now I have two reliable power sources.

Both CPP have minor differences which I now understand to be new large plastic covered capacitors instead of the fade yellow cardboard ones and evidence of modern spade type connectors otherwise identical.

One has a front door on the left hand side to access the 12 to 24 volts knife switch ...the older one requires that you remove the full cover to make the voltage changes.

Thanks Mike for the link to Chris who lives across town from me...... I will always be amazed by information coming from across the globe for something in my own back yard. I have saved the site and will no doubt be doing a lot of reading.

With the help of Stuart Fedak we will be organizing a little radio shack meeting in my sunroom for the Ottawa boys and hope to convince Chris to attend.

Now I have "juice" to play with ....... let's see how far I can progress before blowing a fuse!!!!!

Thanks everyone.

Bob C

[Bruce MacMillan]

The CPP2 is a brute force power supply. That's what makes it good for the 19 set & others that use a dynamotor. There is no electronic regulation so the power supply doesn't shut down with the high inrush current.

The output voltage will drop with load.

I have never seen any docs or a manual for the unit. Wonder if any exist?

[Jon Skagfeld]

Originally Posted by Bob Carriere

EUREKA........Got the CPP 2 working.

So simple yet......

I hunted down a separate used double pole single throw switch from a surplus NRC panel. Tested fine..... ready to be used as a substitute.

Removed the original switch from the CPP 2 and tested again.....seemed to work on one pole....... so being fearless and being that this is pre solid state.... the switch is actually assembled with two screws sealed with some black dry brittle paint. Decided to take the switch apart to see what was defective or broken.... chipped the paint and carefully took it apart laying out the small pieces.... contacts were a bit black and oily...... washed everything in an electrical contact solvent.... bent the contact arm for a bit more pressure and re-assembled...... now works perfectly.

Output dial works and puts out 13.4 to 19 volts in the low range and 26 to
39 volts in the upper range.

Now I have two reliable power sources.

Both CPP have minor differences which I now understand to be new large plastic covered capacitors instead of the fade yellow cardboard ones and evidence of modern spade type connectors otherwise identical.

One has a front door on the left hand side to access the 12 to 24 volts knife switch ...the older one requires that you remove the full cover to make the voltage changes.

Thanks Mike for the link to Chris who lives across town from me...... I will always be amazed by information coming from across the globe for something in my own back yard. I have saved the site and will no doubt be doing a lot of reading.

With the help of Stuart Fedak we will be organizing a little radio shack meeting in my sunroom for the Ottawa boys and hope to convince Chris to attend.

Now I have "juice" to play with ....... let's see how far I can progress before blowing a fuse!!!!!

Thanks everyone.

Bob C

Yeah, "juice" to play with...now watch your hydro meter spin into oblivion!

[Jon Skagfeld]

Originally Posted by Bruce MacMillan

The CPP2 is a brute force power supply. That's what makes it good for the 19 set & others that use a dynamotor. There is no electronic regulation so the power supply doesn't shut down with the high inrush current.

The output voltage will drop with load.

I have never seen any docs or a manual for the unit. Wonder if any exist?

I've been collecting 19 sets and parts for years and never have I seen an operator/user manual for the CPP-2.

BTW, the CPP-2 being a power supply, we always referred to it as a rectifier.

I wonder if the inference was that, as a rectifier, it acted as a step down transformer?

[chris vickery]

Jon, typically a rectifier changes AC current to DC current, and in this case with the CPP-2 it also steps it down from 120VAC to the required 12VDC or 24VDC as needed.
An inverter, on the other hand does just the opposite; DC voltage is changed to AC voltage. Think of using your car battery at 12VDC coupled up to say a 1000w 120VAC inverter to power things like laptops, dvd players etc in your vehicle.
Of course rectifiers or inverters are used in all kinds of applications for relatively low voltage, low amperage uses up to very high, very large industrial uses.
I have most recently worked on rectifiers (135MVA) IIRC in aluminum smelting. These take the supplied line voltage incoming (230,000VAC) and turn it into useable DC current for the potlines.
I believe the potlines main buss runs at 400,000+ Amperes.
Can you say giant bug zapper???

[Bob Carriere]

The design is very basics and massive ....... also very heavy...those side cut outs for handles do not provide a proper grip for lifting...... I am thinking of mounting one on a scaled down furniture dolly so I can wheel it under the work bench without scratching the hard wood floor. The second one will fit nicely on a shelf off the floor underneath the work station.

I got surplus static free electronic work bench some years ago when they shutdown a plant in Kanata....very heavy 1 inch plywood top covered with a 5/16 scuff proof plastic overlay which is grounded to the steel legs......steel panel legs and store shelf underneath. On top of the work bench is a secondary 16 inches high 12 inch back shelf with a full lenght power bar.

Nice tool to play with.

Bob C

[BCA]

My July 1953 Operator's Handbook says the CPP-2 (95 pounds) uses a power transformer followed by 2 metallic rectifiers and smoothing circuits (capacitor choke filter). This produces 2 separate 12 volt, 11 amp power supplies that may be connected by a switch in parallel to give 22 amps @ 12 volts or in series to give 11 amps @ 24 volts. The CCP-5 (129 pounds!) is similar in output but requires a 25 cycle input instead of 60 cycle input. 25 cycle was in common use before the introduction of 60 cycle (Mhtz) power in Canada. (? Late 1940's?).
They are a very useful bench power supply for 12 or 24 volts, although heavy to move around. ... Brian

[Bob Carriere]

...... I will stick to my CPP 2..... which I just carried down the basement to my workshop...... did not realize I was lugging 95 pounds.

Being lazy I have now one CPP 2 set up in the basement workshop and one set up in the sunroom were I do more clean work.....

I still have to set up a variac to slowly power up the 110 volt power supply for the 19 sets.....that I will do in the basement in case I blow up something.

On the Pawnshop TV show today they were powering up a WW II beach head amplifier/speaker set up..... the expert they had brought in had a canister type variac on the floor and was slowly dialing/powering up the old amplifier.... which ran well but had a loud 60 cycle hummmmm .....which he explained was caused by faulty condenser/filters which would need replacing.... and would be costly..... they estimated that the total value of individual parts...tubes.... transformers etc. were worht more than as a total amplifier unit.....

Strange were you can learn new information....

Brian are there any wiring diagrams in your operators manual???

Bob C



.......

[Doug Lavoie]

Bob,
Just saw a CPP-2 power supply on e bay for $249.00 or best offer.Thought that I would not see one like you have been talking about. To bad it is so far south east. The ebay # is: 141123542691.
Doug

[Bob Carriere]

Glad I got mine from MLU members..... at a better price and no shipping,

Bob C

[BCA]

Reasonably priced CPP-2 available for local pickup only: Milton, Ontario. PM me for details. ... Brian