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Space Tech Super Rectifier

Not sure that breaking the glass when it is NOT "in operation" would be very safe. Could shatter explosively, spraying tiny droplets all over the place with smaller ones becoming airborne. The problem then isn't simply the immediate danger. It is being able to decontaminate the room inc furniture, carpets, etc.

Not something I'd use at home.
 
You also need to be aware of the rays the Mercury vapour tubes produce and whether they are harmful being in close proximity to humans.
 
What rays, if you are talking about x-ray, UV, both of these are a non-issue, x-ray won't happen at audio voltages and UV is blocked by the glass. The anode is also bell shaped to block x-ray.
 
Invalid said:
What rays, if you are talking about x-ray, UV, both of these are a non-issue, x-ray won't happen at audio voltages and UV is blocked by the glass. The anode is also bell shaped to block x-ray.
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The mercury glow emits ultraviolet light which is not good for your eyes, especially for prolonged exposure.
 
The glass blocks the UV, if it was as bad as you say, then there would be a lot of old ham radio operators that would have gone blind, and that is not the case.
 
Invalid said:
Then why aren't all the old ham radio guys blind, they sit just a few feet away at max
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I have held a UK class A amateur radio licence since 1979. I have used and operated various radio transmitters over the years, some of which used mercury vapour rectifiers in the HT supply for the output valves. All of that equipment had the MV rectifiers and output tubes enclosed and well shielded, for two reasons, UV emissions from the MV rectifiers, and also, wide band radio frequency interference generated by the MV rectifiers.
 
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Regarding the Space Tech Super Rectifier: I would be extremely careful about using a product like this. Before using one you will need to know exactly what the HT supply voltage will need to be at the current level specified by the amplifier designer. Also, that is a single triode in that power supply (211/VT4-C) which can only be configured as a single diode element. An equivalent rectifier like a 5R4 etc has two diode elements!!! If the single triode (211) is configured as a single diode (it can only be configured as a single diode) then you can only get a half wave rectified output. A 5R4 with 2 diode elements can output a full wave rectified supply. I might be wrong here, but I suspect the power supply is solid state rectified and the 211 triode is used as a pass regulator. Otherwise it can only output half wave rectified DC. As always with products like this, it is Buyer Beware...
 
You can cut on this product all you want without trying it, but it works way better than the standard dual element rectifiers, I know because I have tried it.
 
G T Audio said:
Regarding the Space Tech Super Rectifier: I would be extremely careful about using a product like this. Before using one you will need to know exactly what the HT supply voltage will need to be at the current level specified by the amplifier designer. Also, that is a single triode in that power supply (211/VT4-C) which can only be configured as a single diode element. An equivalent rectifier like a 5R4 etc has two diode elements!!! If the single triode (211) is configured as a single diode (it can only be configured as a single diode) then you can only get a half wave rectified output. A 5R4 with 2 diode elements can output a full wave rectified supply. I might be wrong here, but I suspect the power supply is solid state rectified and the 211 triode is used as a pass regulator. Otherwise it can only output half wave rectified DC. As always with products like this, it is Buyer Beware...
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Apart from which - having such a huge loop area via the cabling from the transformer, via remote rectifier, back to an amplifier - is an utter, utter, mess of generated (and totally-avoidable) EMI (interference, to everyone else) : o

this 'product ' = simple bloody insanity.
 
martin clark said:
Apart from which - having such a huge loop area via the cabling from the transformer, via remote rectifier, back to an amplifier - is an utter, utter, mess of generated (and totally-avoidable) EMI (interference, to everyone else) : o

this 'product ' = simple bloody insanity.
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Well... let's see how it actually sound first before writing it off eh?
 
And another thing...

One of the advantages of a valve rectifier, as in the one fitted in the original amplifiers design, is this provides a slow HT voltage start up due to the filament warming up and creating the conditions for the diode elements to conduct. The slow start from the original valve rectifier means that HT voltage is applied to the amplifiers first capacitor, or capacitors, slowly over a period of approximately 10 to 20 seconds depending on the valve rectifier used. It may take up to 1 minute for the power supply to reach its optimum working conditions. The slow start protects the capacitor(s) and the rest of the amplifier from a sudden turn on. With the Space Tech Super Rectifier, this has to be turned on for 1 minute before switching it from standby to "on". So the voltage hitting the original amplifiers power supply will be instant with no soft start. The instant voltage hitting the amplifiers original capacitor(s) could cause the capacitor(s) to prematurely fail over time. There could also be other issues within the original amplifier design that could occur as a result of the instant HT voltage turn on that the original amplifier designer wouldn't have taken into account, as removing the soft start was not part of the original design. Having a soft start power supply in any valve amplifier is massively advantageous for a long life for many internal amplifier components especially in the power supply.
 
The early versions of the Armstrong 600 range has a 'slow start' circuit. It was a PITA and the main cause of people returning them to be repaired! it also added to the cost. I dumpted it and used better diodes in the rectifier bridge and better PSU caps. Better performance and a reduction in the number of unhappy customers making the 'pilgrimage' for their "whilst you wait" repair at Warlters Rd! :)

You choose components like res caps, diodes, and input tranformer as a package to work together. e.g. transformer saturates with a resistance that ensures the caps and diodes are OK.
 
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