Question on Collins power supply main voltages.
 

I'd like to buy a 75S-3A or 75S3C Collins receiver. On eBay many are on sale
from USA suppliers.
I'm just in doubt because i cannot find clear indication on main power
supply possibilities.
Documentation found on Internet sometimes specify 110/220, other times just
110.
And i need a 220 capable unit, since i'm living in Europe.
Is there a way to detect clearly what is the effective power supply
installed?
I've the same problem also on the 516F-2 power supply.
The only power supply that clearly specify a dual voltage option is the
PM-2.
Is there somebody that can clarify my doubt?
Many thanks.
Mauro

Mauro,

The 516F-2 has a dual primary transformer. The primaries can be wired in
series for 220 volt operation. This is also true of the 30L-1 amplifier and
the 30S-1 amplifier. For the 75S-x receivers which are 110 only according
to
the manuals, you could try several simple approaches. Since it would only
draw 2 to 3 amps at most, a small step down transformer could be used.
Also, you could try something resistive and dissipating 250 watts that would
drop the voltage to the 110 range.

good luck & 73,
Phil
W5BVB

"Mauro Succi" wrote in message
.. .
I'd like to buy a 75S-3A or 75S3C Collins receiver. On eBay many are on
sale
from USA suppliers.
I'm just in doubt because i cannot find clear indication on main power
supply possibilities.
Documentation found on Internet sometimes specify 110/220, other times
just
110.
And i need a 220 capable unit, since i'm living in Europe.
Is there a way to detect clearly what is the effective power supply
installed?
I've the same problem also on the 516F-2 power supply.
The only power supply that clearly specify a dual voltage option is the
PM-2.
Is there somebody that can clarify my doubt?
Many thanks.
Mauro

Tks for the answer. Any idea of KWM-2 and 2A?
mauro
i2suh

Well, last I heard the 516F-2 power supply was used on the KWM-2 and
-2A...... The KWM-2 and 2-A do not have an internal power supply and
like the 32S-x series of transmitters depend on an outboard power supply

73, Phil




"Mauro Succi" wrote in message
.. .
Tks for the answer. Any idea of KWM-2 and 2A?
mauro
i2suh

When I was down under in Oz they used PM-2 on the KWM-2.
73
Hank WD5JFR
"Mauro Succi" wrote in message
.. .
Tks for the answer. Any idea of KWM-2 and 2A?
mauro
i2suh

Be advised that all 516F-2's are not alike. Some earlier, winged units
were for 110v VAC ONLY and did not have split primaries. Be sure and
check before buying, if you need 220v.

Mauro Succi wrote:

I'd like to buy a 75S-3A or 75S3C Collins receiver. On eBay many are on sale
from USA suppliers.
I'm just in doubt because i cannot find clear indication on main power
supply possibilities.
Documentation found on Internet sometimes specify 110/220, other times just
110.
And i need a 220 capable unit, since i'm living in Europe.
Is there a way to detect clearly what is the effective power supply
installed?
I've the same problem also on the 516F-2 power supply.
The only power supply that clearly specify a dual voltage option is the
PM-2.
Is there somebody that can clarify my doubt?
Many thanks.
Mauro

Is there a known S/N when the production switched to split primaries?
Can i assume that all round emblem units have split primaries?
A couple of time I've asked sellers that info, but never got exaustive
answer.
So i'm still waiting to bid.
Mauro

Mauro:

Although the 75S-3 series receivers make no internal provision for 220 volt
AC operation, there is another option in addition to those already
mentioned.

It is possible to feed in the receiver's operating voltages from an external
supply that furnishes filament (6, 12 or 24 volts), +185 and -65 volts DC.
The 11 pin power plug used to feed in 110 volt AC also allows for external
supply voltages to be fed in, bypassing the power transformer. You could
build an external 220 VAC supply for a 75S-3.

A 2:1 step down transformer is clearly the simplest solution, and usually
simplest is best.

73,

Roger K6XQ

Well, my 1965 book (winged) has the 110 only transformer. The 1968 and
subsequent books all show the split primary. Greater Collins minds than
mine will have to give you a serial number relationship. Having said
that, it does appears that a round power supply will have the 110/220
capability. So, if its a round your interested in, I'd bet the ranch
that it'll work on both input voltages.

Mauro Succi wrote:
Is there a known S/N when the production switched to split primaries?
Can i assume that all round emblem units have split primaries?
A couple of time I've asked sellers that info, but never got exaustive
answer.
So i'm still waiting to bid.
Mauro