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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Selenium Rectifier / Metal Rectifier queries
Firstly are they synomynous?
I have a data book , printed in 1933 Westinghouse "the all-metal way" metal rectifiers , how to build High Tension battery eliminators and battery chargers. A 300V , 60mA Westinghouse one in 1933 was about 3x3x5 inches, no mention of Selenium, trade secret then ?. The pic http://home.graffiti.net/diverse:graffiti.net/Se_R.jpg Shows on the right a disassemled one from a 1959 Dansette, one of the two , 8 layer blocks is shown, removed, on end near the ruler (0.1 inch) Single element rectifier Siemens lazy S logo Made in Germany E 250c50 Kc 0.6e 11/16 1979 Siemens databook and E250C50 were still listed, rating 200V, 20mA The book page is from 1967 catalogue. Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#2
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Selenium Rectifier / Metal Rectifier queries
On Jan 9, 8:58*am, "N_Cook" wrote:
Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked Copper oxide was used for quite a while. |
#3
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Selenium Rectifier / Metal Rectifier queries
"TwoMuttHeads" wrote in message ... On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked Copper oxide was used for quite a while. Yes. I was going to say exactly the same thing. I think that the original "metal" rectifier, was a copper oxide device, rather than selenium. It's been a long time ago now, but I seem to remember back in my yoof when I was an apprentice, that we talked of metal rectifiers and selenium rectifiers as different entities. Arfa |
#4
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Selenium Rectifier / Metal Rectifier queries
Arfa Daily wrote in message
... "TwoMuttHeads" wrote in message ... On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked Copper oxide was used for quite a while. Yes. I was going to say exactly the same thing. I think that the original "metal" rectifier, was a copper oxide device, rather than selenium. It's been a long time ago now, but I seem to remember back in my yoof when I was an apprentice, that we talked of metal rectifiers and selenium rectifiers as different entities. Arfa I'm trying to find if any sort of (presumably) non-thermionic rectifier could fit in a space 95x70x12 mm in the 1940s. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#5
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Selenium Rectifier / Metal Rectifier queries
On Fri, 9 Jan 2009 15:58:28 -0000, "N_Cook" put
finger to keyboard and composed: Firstly are they synomynous? I have a data book , printed in 1933 Westinghouse "the all-metal way" metal rectifiers , Search for US patents containing the terms "metal rectifier" and which are assigned to Westinghouse: http://www.google.com/patents?as_q=&...maxy_ap=20 09 http://preview.tinyurl.com/9aqglu For example, US patent 2,802,158 (Aug 6, 1957) refers to "metal rectifier elements which may be selenium rectifiers": http://www.google.com/patents/pdf/ME...xvHOk3IZmdgL0g http://preview.tinyurl.com/9qtwc4 This suggests that selenium rectifiers were just one type of metal rectifier. Other patents refer more generally to "metal-oxide rectifiers": http://www.google.com/patents/pdf/ME...eyz3OVvVUaJjTg http://preview.tinyurl.com/8yphxt - Franc Zabkar -- Please remove one 'i' from my address when replying by email. |
#6
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Selenium Rectifier / Metal Rectifier queries
On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked TwoMuttHeads wrote: Copper oxide was used for quite a while. The "whistle" rectifier in Lionel train transformers of the 1950s were copper oxide. |
#7
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Selenium Rectifier / Metal Rectifier queries
"N_Cook" wrote in message ... Arfa Daily wrote in message ... "TwoMuttHeads" wrote in message ... On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked Copper oxide was used for quite a while. Yes. I was going to say exactly the same thing. I think that the original "metal" rectifier, was a copper oxide device, rather than selenium. It's been a long time ago now, but I seem to remember back in my yoof when I was an apprentice, that we talked of metal rectifiers and selenium rectifiers as different entities. Arfa I'm trying to find if any sort of (presumably) non-thermionic rectifier could fit in a space 95x70x12 mm in the 1940s. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ Are you trying to figure out what was in there originally or just want something to fit? I suspect the former since a silicon rectifier, probably with series dropping resistor would work to replace a metal-oxide rectifier. It seems to me that selenium stack rectifiers were not used before about 1945. Copper oxide rectifers were used in "battery eliminators" and were the standard rectifiers in AC meters. I don't think either is made any more but either can be replaced with silicon rectifiers. -- -- Richard Knoppow Los Angeles WB6KBL |
#8
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Selenium Rectifier / Metal Rectifier queries
"Carter" wrote in message ... On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked TwoMuttHeads wrote: Copper oxide was used for quite a while. The "whistle" rectifier in Lionel train transformers of the 1950s were copper oxide. |
#9
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Selenium Rectifier / Metal Rectifier queries
I don't think either is made any more but either can
be replaced with silicon rectifiers. -- -- Richard Knoppow Los Angeles WB6KBL I believe Selenium is still used in the power industry. http://www.cehco.com/?page_id=233 Paul P. |
#10
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Selenium Rectifier / Metal Rectifier queries
Richard Knoppow wrote in message
... "N_Cook" wrote in message ... Arfa Daily wrote in message ... "TwoMuttHeads" wrote in message ... On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked Copper oxide was used for quite a while. Yes. I was going to say exactly the same thing. I think that the original "metal" rectifier, was a copper oxide device, rather than selenium. It's been a long time ago now, but I seem to remember back in my yoof when I was an apprentice, that we talked of metal rectifiers and selenium rectifiers as different entities. Arfa I'm trying to find if any sort of (presumably) non-thermionic rectifier could fit in a space 95x70x12 mm in the 1940s. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ Are you trying to figure out what was in there originally or just want something to fit? I suspect the former since a silicon rectifier, probably with series dropping resistor would work to replace a metal-oxide rectifier. It seems to me that selenium stack rectifiers were not used before about 1945. Copper oxide rectifers were used in "battery eliminators" and were the standard rectifiers in AC meters. I don't think either is made any more but either can be replaced with silicon rectifiers. -- -- Richard Knoppow Los Angeles WB6KBL I am trying to recusitate a tiny wartime 'scope that someone in the late 60s/70s must have changed to a couple of Si diodes to keep working http://home.graffiti.net/diverse:gra.../miniscope.htm but an "enigma" hinges on whether 2 rectifiers could be squashed into that space either side of the pentode in the 1940s. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#11
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Selenium Rectifier / Metal Rectifier queries
Another term you may hear is "dry rectifier". This can refer to either
a copper oxide or selenium rectifier, but more often to copper oxide since electrolytic rectifiers (very wet) were long gone by the time seleniums came around. N_Cook wrote: Firstly are they synomynous? I have a data book , printed in 1933 Westinghouse "the all-metal way" metal rectifiers , how to build High Tension battery eliminators and battery chargers. A 300V , 60mA Westinghouse one in 1933 was about 3x3x5 inches, no mention of Selenium, trade secret then ?. The pic http://home.graffiti.net/diverse:graffiti.net/Se_R.jpg Shows on the right a disassemled one from a 1959 Dansette, one of the two , 8 layer blocks is shown, removed, on end near the ruler (0.1 inch) Single element rectifier Siemens lazy S logo Made in Germany E 250c50 Kc 0.6e 11/16 1979 Siemens databook and E250C50 were still listed, rating 200V, 20mA The book page is from 1967 catalogue. Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ -- Jim Mueller To get my real email address, replace wrongname with dadoheadman. Then replace nospam with fastmail. Lastly, replace com with us. |
#12
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Selenium Rectifier / Metal Rectifier queries
Copper oxide was used for years in movie theaters as rectifiers for
the exciter lamp power supplies in the soundheads. |
#13
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Selenium Rectifier / Metal Rectifier queries
Ken Layton wrote in message
... Copper oxide was used for years in movie theaters as rectifiers for the exciter lamp power supplies in the soundheads. The second to last page of the 1933 Westinghouse book refers to 2 units pictured being used in ""talkie" installations" , but nowhere in the book is there reference to either CuO or Se, just metal rectifiers. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#14
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Selenium Rectifier / Metal Rectifier queries
On Fri, 9 Jan 2009 15:58:28 -0000, "N_Cook" put
finger to keyboard and composed: Firstly are they synomynous? I have a data book , printed in 1933 Westinghouse "the all-metal way" metal rectifiers , how to build High Tension battery eliminators and battery chargers. A 300V , 60mA Westinghouse one in 1933 was about 3x3x5 inches, no mention of Selenium, trade secret then ?. FWIW, here are some patents of around that time: SOLID RECTIFYING ELEMENT US Pat. 2030443 - Filed Jul 19, 1934 In order to assure a perfect operation of a selenium rectifier ... RAILWAY TKACK CIRCUIT APPARATUS US Pat. 2015577 - Filed Nov 9, 1934 - The Union Switch a Signal Company As is well known, the copper oxide rectifier (as 05 well as certain other rectifiers of this type, such as the selenium rectifier) ... ELECTRICAL DEVICE US Pat. 2124306 - Filed Jul 17, 1935 - International Standard Electric Corporation A method of manufacturing a selenium rectifier having upper and lower metallic members which comprises applying selenium to the- lower member, ... METHOD OF PRODUCING SELENIUM US Pat. 2121603 - Filed Apr 14, 1937 - The above described treatment of selenium rectifier plates with reducing materials may be applied if necessary to plates of the type in which the selenium ... The pic http://home.graffiti.net/diverse:graffiti.net/Se_R.jpg Shows on the right a disassemled one from a 1959 Dansette, one of the two , 8 layer blocks is shown, removed, on end near the ruler (0.1 inch) Single element rectifier Siemens lazy S logo Made in Germany E 250c50 Kc 0.6e 11/16 1979 Siemens databook and E250C50 were still listed, rating 200V, 20mA The book page is from 1967 catalogue. Here is a 1931 Siemens patent: APPARATUS FOB CONTROLLING ELEC US Pat. 1929216 - Filed Apr 1, 1931 - Siemens a Habke .... there occurs a change in the resistance of the individual valves, which may be dry rectifier valves, such as copper oxide or selenium valves, ... Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked - Franc Zabkar -- Please remove one 'i' from my address when replying by email. |
#15
Posted to rec.antiques.radio+phono,sci.electronics.repair
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Selenium Rectifier / Metal Rectifier queries
Franc Zabkar wrote in message
... On Fri, 9 Jan 2009 15:58:28 -0000, "N_Cook" put finger to keyboard and composed: Firstly are they synomynous? I have a data book , printed in 1933 Westinghouse "the all-metal way" metal rectifiers , how to build High Tension battery eliminators and battery chargers. A 300V , 60mA Westinghouse one in 1933 was about 3x3x5 inches, no mention of Selenium, trade secret then ?. FWIW, here are some patents of around that time: SOLID RECTIFYING ELEMENT US Pat. 2030443 - Filed Jul 19, 1934 In order to assure a perfect operation of a selenium rectifier ... RAILWAY TKACK CIRCUIT APPARATUS US Pat. 2015577 - Filed Nov 9, 1934 - The Union Switch a Signal Company As is well known, the copper oxide rectifier (as 05 well as certain other rectifiers of this type, such as the selenium rectifier) ... ELECTRICAL DEVICE US Pat. 2124306 - Filed Jul 17, 1935 - International Standard Electric Corporation A method of manufacturing a selenium rectifier having upper and lower metallic members which comprises applying selenium to the- lower member, ... METHOD OF PRODUCING SELENIUM US Pat. 2121603 - Filed Apr 14, 1937 - The above described treatment of selenium rectifier plates with reducing materials may be applied if necessary to plates of the type in which the selenium ... The pic http://home.graffiti.net/diverse:graffiti.net/Se_R.jpg Shows on the right a disassemled one from a 1959 Dansette, one of the two , 8 layer blocks is shown, removed, on end near the ruler (0.1 inch) Single element rectifier Siemens lazy S logo Made in Germany E 250c50 Kc 0.6e 11/16 1979 Siemens databook and E250C50 were still listed, rating 200V, 20mA The book page is from 1967 catalogue. Here is a 1931 Siemens patent: APPARATUS FOB CONTROLLING ELEC US Pat. 1929216 - Filed Apr 1, 1931 - Siemens a Habke ... there occurs a change in the resistance of the individual valves, which may be dry rectifier valves, such as copper oxide or selenium valves, ... Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked - Franc Zabkar -- Please remove one 'i' from my address when replying by email. What sort of UK names of components catalogues that included non-valve parts of the 1940s , was Radio Spares going then ? Perhaps I should try and find a 1940s Westinghouse cat. -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#16
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Selenium Rectifier / Metal Rectifier queries
2 Selenium rectifier trade names of the right sort of specs, of the early
1950s, were Westinghouse Westalite and STC SenTerCel for which the earliest reference I've found is 1951 -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#17
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Selenium Rectifier / Metal Rectifier queries
according to ebay
http://i16.ebayimg.com/05/i/000/88/e0/2dc0_2.JPG is a WAR DEPT!! WESTALITE RECTIFIER,NORTON, TRIUMPH, MATCHLESS etc... Straight from the War Department. Genuine NOS Military parts removed from 'jungle paper' Rectifier Made in England By Westinghouse Brake & Signal Co Ltd. Pat 620102 & others. Cat No. 2L 985. Positive Case. 98mm x 98mm x 12mm. When did "war dept" cease ? At least another patent number to research -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#18
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Selenium Rectifier / Metal Rectifier queries
http://www.wikipatents.com/gb/0620102.html
for UK patent 620102, 1947, is about rectifier construction/gaskets but refers to "well known selenium type" -- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on http://home.graffiti.net/diverse:graffiti.net/ |
#19
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Selenium Rectifier / Metal Rectifier queries
On Jan 9, 12:23*pm, Carter wrote:
On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked TwoMuttHeads wrote: Copper oxide was used for quite a while. The "whistle" rectifier in Lionel train transformers of the 1950s were copper oxide. Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Dwight |
#20
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Selenium Rectifier / Metal Rectifier queries
On Wed, 14 Jan 2009 22:08:38 -0000, "N_Cook"
wrote: 2 Selenium rectifier trade names of the right sort of specs, of the early 1950s, were Westinghouse Westalite and STC SenTerCel for which the earliest reference I've found is 1951 Selenium rectifiers date from the mid to late 20's I believe. Kevin |
#21
Posted to rec.antiques.radio+phono,sci.electronics.repair
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Selenium Rectifier / Metal Rectifier queries
In article
, " in sci.electronics.repair wrote: On Jan 9, 12:23Â*pm, Carter wrote: On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked TwoMuttHeads wrote: Copper oxide was used for quite a while. The "whistle" rectifier in Lionel train transformers of the 1950s were copper oxide. Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. Regards, David P. |
#22
Posted to rec.antiques.radio+phono,sci.electronics.repair
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Selenium Rectifier / Metal Rectifier queries
On Jan 16, 12:23 pm, David Powell wrote:
In article , " in sci.electronics.repair wrote: On Jan 9, 12:23 pm, Carter wrote: On Jan 9, 8:58 am, "N_Cook" wrote: Firstly are they synomynous? Would the English military have had access to these size and sort of ratings, of the later rectifiers, in 1940s, they could have been heatsinked TwoMuttHeads wrote: Copper oxide was used for quite a while. The "whistle" rectifier in Lionel train transformers of the 1950s were copper oxide. Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. Regards, David P. Yep! Dwight |
#23
Posted to rec.antiques.radio+phono,sci.electronics.repair
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Selenium Rectifier / Metal Rectifier queries
In article ,
David Powell wrote: In article , " in Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. I thought the rectifiers used in the old VU meters, as well as various telephony applications, were Copper Oxide? If Copper Oxide doesn't work in audio frequency applications what sort of rectifier stacks were used in these audio applications? -- Regards, John Byrns Surf my web pages at, http://fmamradios.com/ |
#24
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Selenium Rectifier / Metal Rectifier queries
In article
, John Byrns in sci.electronics.repair wrote: In article , David Powell wrote: In article , " in Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. I thought the rectifiers used in the old VU meters, as well as various telephony applications, were Copper Oxide? If Copper Oxide doesn't work in audio frequency applications what sort of rectifier stacks were used in these audio applications? Dunno about old VU meters, but my guess is that they're rather different to the meters and battery chargers that were the topic, in that there will be amplification in the system. Given that, whatever the response curve of the widget is, it can be linearized as necessary with appropriate filters. My comment described a characteristic of the nekkid rectifier. It's not that they don't work at audio, just that they will only be accurate over a very restricted frequency range. Not that I've a high opinion on VU meters as used in typical consumer electronics, unlikely to even equal the accuracy of my car's fuel tank contents gauge. Might as well wire a filament lamp across the speakers and measure with a light meter. Regards, David P. |
#25
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Selenium Rectifier / Metal Rectifier queries
"David Powell" wrote in message news In article , John Byrns in sci.electronics.repair wrote: In article , David Powell wrote: In article , " in Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. I thought the rectifiers used in the old VU meters, as well as various telephony applications, were Copper Oxide? If Copper Oxide doesn't work in audio frequency applications what sort of rectifier stacks were used in these audio applications? Big plates like in battery chargers = big capacitance = poor audio response. Very small plates like in meters = small capacitance = good audio response. David |
#26
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Selenium Rectifier / Metal Rectifier queries
In article ,
"David" wrote: "David Powell" wrote in message news In article , John Byrns in sci.electronics.repair wrote: In article , David Powell wrote: In article , " in Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. I thought the rectifiers used in the old VU meters, as well as various telephony applications, were Copper Oxide? If Copper Oxide doesn't work in audio frequency applications what sort of rectifier stacks were used in these audio applications? Big plates like in battery chargers = big capacitance = poor audio response. Very small plates like in meters = small capacitance = good audio response. I'll buy that. -- Regards, John Byrns Surf my web pages at, http://fmamradios.com/ |
#27
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Selenium Rectifier / Metal Rectifier queries
John Byrns wrote:
In article , "David" wrote: "David Powell" wrote in message news In article , John Byrns in sci.electronics.repair wrote: In article , David Powell wrote: In article , " in Hi Copper Oxide have the advantage for things like meters and battery charges because they have a low forward voltage drop. The primary problem is that it has a very low reverse voltage. Even in charger applications, it took a stack of many junctions to hold off the reverse voltage of a 12volt charger. Their downside for meter use is low bandwidth. Fine for a 50 / 60 Hz electrician's testmeter, useless for audio. Often way off at 400 Hz. I thought the rectifiers used in the old VU meters, as well as various telephony applications, were Copper Oxide? If Copper Oxide doesn't work in audio frequency applications what sort of rectifier stacks were used in these audio applications? Big plates like in battery chargers = big capacitance = poor audio response. Very small plates like in meters = small capacitance = good audio response. I'll buy that. The copper oxide meter rectifiers I have seen are about 3/16" in diameter. The one in the battery charger I have is about 2" X 4". -- Jim Mueller To get my real email address, replace wrongname with dadoheadman. Then replace nospam with fastmail. Lastly, replace com with us. |
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