A very simple question! Does anyone know/remember if the mains transformers on these amps can be reconnected to take 230-240vAC mains electricity? If so I shall be delighted to hear - either way - as I have an opportunity to acquire one which appears to be in good condition!
I would also very much welcome a copy of the circuit schematic....please.
[Are you out there Zen MOD????
]
Many thanks.
I would also very much welcome a copy of the circuit schematic....please.
[Are you out there Zen MOD????
]Many thanks.
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....
[Are you out there Zen MOD????
.......
I am ...... but who needs me , when real McCoy is there , too .......
(even if schm looks as borrowed from this ACME Gentleman )
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By a CAS-1 exemplar that I had to repair service 2 years ago, it was possible to set both 115V and 220V main voltage (see my own created pdf schematic include power supply transformer).
On the other hand, I cannot rule out, that there are versions (only for the us marked e. g.), where only one primary winding is present for 110VAC mains voltage.
If you have such version, you need an additional isolation transformer from 220-240V VAC to 110 VAC !!! Otherwise, the built-in transformer would be destroyed.
Check the number of windings, and connections on the primary side of transformer in your exemplar - the power supply schematic of CAS-1 could be helpful
I discover a currently ebay auction: Item number: 270510641211
On the other hand, I cannot rule out, that there are versions (only for the us marked e. g.), where only one primary winding is present for 110VAC mains voltage.
If you have such version, you need an additional isolation transformer from 220-240V VAC to 110 VAC !!! Otherwise, the built-in transformer would be destroyed.
Check the number of windings, and connections on the primary side of transformer in your exemplar - the power supply schematic of CAS-1 could be helpful
I discover a currently ebay auction: Item number: 270510641211
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I have a prototype CAS-2 I purchased from local store when I lived in Pilot Hill, Ca. Front panel has no markings. Only thing on front panel is power switch and power-on LED. Back panel is complete and marked including stick-on label, but without any SN, date, etc - just blank.
My CAS-2 has only one power supply transformer, one bridge rectifier and eight large capacitors. The primary has three black wires, only two are connected for 115VAC. This transformer is slightly thicker than the ones in my CAS-1's.
From pictures on internet, production CAS-2 had two transformers, two bridges and 2 sets of capacitors. Also had LED meter on front panel.
I also have schematic of CAS-2 I got from Threshold applications engineer in 1990. Schematic is in California, I am in Florida until May.
CAS-2 has three TO-3's as output cascode devices. CAS-1 has two.
CAS-2 has two TO-3's as output devices. CAS-1 has one. Rest of circuit is the same, excepting some resistor values and capacitor values.
Schematic has + and - 57v supply. My CAS-2 measures + and - 50v.
Sorry, but don't think I answered your question.
My CAS-2 has only one power supply transformer, one bridge rectifier and eight large capacitors. The primary has three black wires, only two are connected for 115VAC. This transformer is slightly thicker than the ones in my CAS-1's.
From pictures on internet, production CAS-2 had two transformers, two bridges and 2 sets of capacitors. Also had LED meter on front panel.
I also have schematic of CAS-2 I got from Threshold applications engineer in 1990. Schematic is in California, I am in Florida until May.
CAS-2 has three TO-3's as output cascode devices. CAS-1 has two.
CAS-2 has two TO-3's as output devices. CAS-1 has one. Rest of circuit is the same, excepting some resistor values and capacitor values.
Schematic has + and - 57v supply. My CAS-2 measures + and - 50v.
Sorry, but don't think I answered your question.
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Thanks for the pictures.
I would think you could rewire the 115v primary of each transformer to be in series, just like the "tiefbassuebertr" power supply schematic shows. The two primary's must be wired in parallel for 115vac operation.
I'm listening to my CAS-2 right now. Have never considered another amplifier.
Contrary to what you read as output power. CAS-2 was rated at 75 watts (8 ohm load) for low distortion and 100 watts for high distortion. Output voltage will start to limit at 90 watts.
I would think you could rewire the 115v primary of each transformer to be in series, just like the "tiefbassuebertr" power supply schematic shows. The two primary's must be wired in parallel for 115vac operation.
I'm listening to my CAS-2 right now. Have never considered another amplifier.
Contrary to what you read as output power. CAS-2 was rated at 75 watts (8 ohm load) for low distortion and 100 watts for high distortion. Output voltage will start to limit at 90 watts.
brianco - seems that you're one lucky bstrd
(NB that I didn't say that you don't deserve that
But first, JamesBrennan4 & tiefbassuebertr:
That is excellent info. and enough for me to take a risk! ( I actually have a 1.5K isolation Tx anyway, but I dont like all that extra magnetism, cabling etc.) Thank you all for your kind trouble and input.
ZM: Send me US$ 250:00 and I will send you an Irish Luck Charm.....but I will have drunk the black stuff - just to save on post stamp cost you understand!
....I am almost finished assembling my kitchen system! Just need a decent CD transport and a phonostage!
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If for the primary winding at least three wires, you can check the DC resistances for it (Please disconnect from main connector). You must find then two different values of DC resistance. The highest value must be approximately twice than the lowest value.
If you have more than three wires, means this more selected voltages are possible (e. g. 110-115-220-230VAC)
Use in this case the highest possible value for your main voltage (now all primary windings in series).
Check all this without the other stuff - i. e. only transformer without connected secondary winding.
If for the primary winding only two wires, I assume, you have transformer for only 110-115VAC
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All,Here's what I've got:
I just picked up 2 CAS2.
It doesn't have anything on front either but these are made to be mono amps with 1 circuit board and 1 transformer but with 4 large capacitors.
The back is still the same CAS2 marking but the input and output are joint.
No serial number.
Are these monoblocks specially built?
The logo on front says customer series
anyone know? These are in Silicon Valley.
Hi everyone,
So I have a near perfect CAS2. I have changed all the caps out, including the main PS caps, and it sounds brilliant and has worked without a hitch for a couple of years. Unfortunately, however, just recently the right channel of the level meter has stopped working properly with all the LEDs lit up. The left channel, and the amplifier itself, are still working properly.
Would anyone here have any tips as to what part has gone bad? Is it an integrated chip of some kind or a discrete part? If the former, might it or some equivalent still be made?
Thanks and best regards!
So I have a near perfect CAS2. I have changed all the caps out, including the main PS caps, and it sounds brilliant and has worked without a hitch for a couple of years. Unfortunately, however, just recently the right channel of the level meter has stopped working properly with all the LEDs lit up. The left channel, and the amplifier itself, are still working properly.
Would anyone here have any tips as to what part has gone bad? Is it an integrated chip of some kind or a discrete part? If the former, might it or some equivalent still be made?
Thanks and best regards!
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