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Re: SR2000 and P2000 restoration continues
Walt said: ?A capacitor that is run at less than its specified voltage will reform at the lower voltage* and yield less capacitance**. *I agree with this statement, at a lower working voltage, the dielectric will reform to that lower working voltage.? But the capacitor is still capable of being reformed to operate at the originally rated standoff voltage. **Voltage across the capacitor has no affect on capacitance, the operating voltage is not in the formula used to solve for capacitance, that formula is simply plate surface area divided by plate separation. An aluminum electrolytic capacitor will maintain the same capacitance at any voltage below it's rated withstanding voltage.? The thickness of the dielectric, the insulator made by oxidation of the etched aluminum surface, also determines the withstanding voltage.? This oxide will deteriorate over time and allow a leakage current to flow.? This is what the reforming process corrects.?? The electrolyte is the "second plate" of the capacitor, not the second piece of aluminum foil.? Being a paste, it will conform to the etched oxidated surface of the primary aluminum foil.? The second aluminum foil is there only to make contact with the electrolyte.? Since both the second aluminum plate and the electrolyte are at the same relative potential, there is no capacitance between them.? But it is a lossy electrode so there is a resistance associated with the electrolyte & foil pair, aka ESR. Don, if the two references below did not answer your questions, then perhaps an internet search will find a explanation to your liking for how aluminum electrolytic capacitors work. Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Saturday, May 4, 2024 at 08:29:12 PM CDT, don Root <drootofallevil@...> wrote:
Jim? I am now confused about just what has been in question. Your comments seem good, but don’t seem to address Walt’s comments.IMO of course. What Walt seems to be suggesting is new to me. I would like to see that clarified for us hard of hearing guys, ?and maybe see an authentic source of that thinking so I can repeat it with some confidence. ? From: [email protected] [mailto:[email protected]] On Behalf Of Jim Whartenby via groups.io
Sent: Saturday, May 4, 2024 5:09 PM To: [email protected] Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ? Electrolytic has to do with the flow of current through a liquid, nothing more.? What we now know as an electrolytic capacitor started out as a detector?in early days of radio and?as a means of changing AC to DC. See:?? ? The insulating material, the dielectric, in an aluminum electrolytic capacitor is aluminum oxide.? The electrolyte serves as a connection on the far side of that oxide.? ?The electrolyte conforms to all of the nooks and crannies of the oxidized aluminum sheet that was etched to increase the surface area.? So the conductors in an aluminum electrolytic capacitor are the etched aluminum and the electrolyte.? Between these two conductors is the aluminum oxide.? The second aluminum sheet is a means to connect the electrolyte to the capacitor terminal.? See: ? Regards, Jim ? Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Saturday, May 4, 2024 at 02:29:39 PM CDT, waltcates <cateswa@...> wrote: ? ? We were talking about the working voltage of electrolytics. The applied voltage on an electrolytic capacitor does in fact affect?the dielectric constant of the capacitor. Hense the name "Electrolytic". ? ? Walt Cates, WD0GOF ? A majority of acceptance is not proof of correctness. ? From: [email protected] <[email protected]> on behalf of Jim Whartenby via groups.io <old_radio@...> ? AFAIK, withstanding voltage has little to no affect on capacitance.? Capacitance is plate area vs dielectric thickness.? I have seen capacitors test within their capacitance tolerance but fail for withstanding voltage way below the rated value. ? If the dielectric reforms to a lower withstanding voltage, would not the dielectric be thinner?? A thinner dielectric would indicate a higher capacitance, would it not? Regards, Jim ? Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Saturday, May 4, 2024 at 12:47:32 PM CDT, W7WRX <clark@...> wrote: ? ? Good point ? This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it on a terminal strip. The can cap is dated 1967.?? ? These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time. ? C ? C ? On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote: One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec. ? A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance. ? ? ? ? ? Walt Cates, WD0GOF ? A majority of acceptance is not proof of correctness. ? From: [email protected] <[email protected]> on behalf of W7WRX <clark@...> ? The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
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Re: HT-44 noise on SSB
开云体育Floyd, The HT-44 is out of my ball park, but those rivets are everywhere. Why not try measuring the ohms from the socket [whatever pin needs the ground] to the chassis using a good meter for the job, and sharp, clean probes. That should check the contacts on both sides of the rivet. Likely an analog meter is best to detect likely erratic problems. ? From: [email protected] [mailto:[email protected]] On Behalf Of Floyd - K8AC
Sent: Saturday, May 4, 2024 7:20 PM To: [email protected] Subject: Re: [HallicraftersRadios] HT-44 noise on SSB ? While shorting the mic connector mic lead to ground didn't eliminate the noise, shorting the hot lead to ground for either of the coax runs to the mic level control kills the noise completely.? I installed new teflon coax runs from the audio stages to the mic level control and while that made a very minor but measurable decrease in the noise, it's still very strong.? The teflon coax makes it easier to undo ground connections if I do that. Sounds like either a bad ground connection through one of the riveted terminal strips, or maybe one of the shield connections might need to be lifted from ground, although they were all originally grounded.? If I go that route, any advice on which end to lift the ground from - one end of each coax goes to the front panel mic level pot and the other ends go to the audio stage tubes. _._,_._,_ -- don??? va3drl |
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Re: SR2000 and P2000 restoration continues
开云体育Jim? I am now confused about just what has been in question. Your comments seem good, but don’t seem to address Walt’s comments.IMO of course. What Walt seems to be suggesting is new to me. I would like to see that clarified for us hard of hearing guys, ?and maybe see an authentic source of that thinking so I can repeat it with some confidence. ? From: [email protected] [mailto:[email protected]] On Behalf Of Jim Whartenby via groups.io
Sent: Saturday, May 4, 2024 5:09 PM To: [email protected] Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ? Electrolytic has to do with the flow of current through a liquid, nothing more.? What we now know as an electrolytic capacitor started out as a detector?in early days of radio and?as a means of changing AC to DC. See:?? ? The insulating material, the dielectric, in an aluminum electrolytic capacitor is aluminum oxide.? The electrolyte serves as a connection on the far side of that oxide.? ?The electrolyte conforms to all of the nooks and crannies of the oxidized aluminum sheet that was etched to increase the surface area.? So the conductors in an aluminum electrolytic capacitor are the etched aluminum and the electrolyte.? Between these two conductors is the aluminum oxide.? The second aluminum sheet is a means to connect the electrolyte to the capacitor terminal.? See: ? Regards, Jim ? Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Saturday, May 4, 2024 at 02:29:39 PM CDT, waltcates <cateswa@...> wrote: ? ? We were talking about the working voltage of electrolytics. The applied voltage on an electrolytic capacitor does in fact affect?the dielectric constant of the capacitor. Hense the name "Electrolytic". ? ? Walt Cates, WD0GOF ? A majority of acceptance is not proof of correctness. ? From: [email protected] <[email protected]> on behalf of Jim Whartenby via groups.io <old_radio@...> ? AFAIK, withstanding voltage has little to no affect on capacitance.? Capacitance is plate area vs dielectric thickness.? I have seen capacitors test within their capacitance tolerance but fail for withstanding voltage way below the rated value. ? If the dielectric reforms to a lower withstanding voltage, would not the dielectric be thinner?? A thinner dielectric would indicate a higher capacitance, would it not? Regards, Jim ? Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy ? ? On Saturday, May 4, 2024 at 12:47:32 PM CDT, W7WRX <clark@...> wrote: ? ? Good point ? This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it on a terminal strip. The can cap is dated 1967.?? ? These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time. ? C ? C ? On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote: One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec. ? A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance. ? ? ? ? ? Walt Cates, WD0GOF ? A majority of acceptance is not proof of correctness. ? From: [email protected] <[email protected]> on behalf of W7WRX <clark@...> ? The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000 _._,_._,_
-- don??? va3drl |
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Re: HT-44 noise on SSB
While shorting the mic connector mic lead to ground didn't eliminate the noise, shorting the hot lead to ground for either of the coax runs to the mic level control kills the noise completely.? I installed new teflon coax runs from the audio stages to the mic level control and while that made a very minor but measurable decrease in the noise, it's still very strong.? The teflon coax makes it easier to undo ground connections if I do that. Sounds like either a bad ground connection through one of the riveted terminal strips, or maybe one of the shield connections might need to be lifted from ground, although they were all originally grounded.? If I go that route, any advice on which end to lift the ground from - one end of each coax goes to the front panel mic level pot and the other ends go to the audio stage tubes.
73, K8AC |
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Re: SR2000 and P2000 restoration continues
Electrolytic has to do with the flow of current through a liquid, nothing more.? What we now know as an electrolytic capacitor started out as a detector?in early days of radio and?as a means of changing AC to DC. See:?? The insulating material, the dielectric, in an aluminum electrolytic capacitor is aluminum oxide.? The electrolyte serves as a connection on the far side of that oxide.? ?The electrolyte conforms to all of the nooks and crannies of the oxidized aluminum sheet that was etched to increase the surface area.? So the conductors in an aluminum electrolytic capacitor are the etched aluminum and the electrolyte.? Between these two conductors is the aluminum oxide.? The second aluminum sheet is a means to connect the electrolyte to the capacitor terminal.? See: Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Saturday, May 4, 2024 at 02:29:39 PM CDT, waltcates <cateswa@...> wrote:
We were talking about the working voltage of electrolytics. The applied voltage on an electrolytic capacitor does in fact affect?the dielectric constant of the capacitor. Hense the name "Electrolytic".
Walt Cates, WD0GOF
?
A majority of acceptance is not proof of correctness.
From: [email protected] <[email protected]> on behalf of Jim Whartenby via groups.io <old_radio@...>
Sent: Saturday, May 4, 2024 1:56 PM To: [email protected] <[email protected]> Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
AFAIK, withstanding voltage has little to no affect on capacitance.? Capacitance is plate area vs dielectric thickness.? I have seen capacitors test within their capacitance tolerance but fail for withstanding voltage way
below the rated value.
If the dielectric reforms to a lower withstanding voltage, would not the dielectric be thinner?? A thinner dielectric would indicate a higher capacitance, would it not?
Regards,
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Saturday, May 4, 2024 at 12:47:32 PM CDT, W7WRX <clark@...> wrote:
Good point
This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it on a terminal
strip. The can cap is dated 1967.??
These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time.
C
C
On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote:
One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec.
A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance.
Walt Cates,
WD0GOF
?
A majority of acceptance is not proof of correctness.
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:01 PM To: [email protected] <[email protected]> Subject: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
The high voltage meter was reading way low.? I took the supply apart. Cleaned it, removed the meter bezel and adjusted the needles to zero. They where both below the lines Next I found the smaller of the two 2 Meg meter resistors was reading 7.5meg!? ?I replaced it and now the meter reads correctly. I used my fluke HV probe to find 2050 volts low and 2950 volts high.? I also found screen at 320 low and 426 high.? My line voltage is 126 today. The PS had been recapped but the can cap and the screen cap where factory.? I replaced the screen with a new 20mfd 500 volt sprauge.? I don't have the can cap.? I do have a 30/30 at 450 volt FT cap.? It's very high quality.? I have reservations about running 426 volts on a 450 cap though.? Maybe I get look at the data sheet.? Otherwise I will have to order 500volt caps. |
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Re: HT-44 idle current drift
On Tue, Apr 30, 2024 at 03:35 PM, k2orsfan wrote:
Are the two 6DQ5s balanced? You can check by removing oneThat may be true of your HT-44, but it certainly isn't true of mine.? My 6DQ5s have their filaments in SERIES, so removing one tube removes the filament voltage from the other.? The correct procedure involves removing the screen voltage from one of the tubes, as documented in the Errata Sheet (Form number 094-903794B). 73, Floyd - K8AC |
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Re: SR2000 and P2000 restoration continues
开云体育
We were talking about the working voltage of electrolytics. The applied voltage on an electrolytic capacitor does in fact affect?the dielectric constant of the capacitor. Hense the name "Electrolytic".
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of Jim Whartenby via groups.io <old_radio@...>
Sent: Saturday, May 4, 2024 1:56 PM To: [email protected] <[email protected]> Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
AFAIK, withstanding voltage has little to no affect on capacitance.? Capacitance is plate area vs dielectric thickness.? I have seen capacitors test within their capacitance tolerance but fail for withstanding voltage way
below the rated value.
If the dielectric reforms to a lower withstanding voltage, would not the dielectric be thinner?? A thinner dielectric would indicate a higher capacitance, would it not?
Regards,
Jim
Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Saturday, May 4, 2024 at 12:47:32 PM CDT, W7WRX <clark@...> wrote:
Good point
This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it on a terminal
strip. The can cap is dated 1967.??
These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time.
C
C
On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote:
One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec.
A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance.
Walt Cates,
WD0GOF
?
A majority of acceptance is not proof of correctness.
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:01 PM To: [email protected] <[email protected]> Subject: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
The high voltage meter was reading way low.? I took the supply apart. Cleaned it, removed the meter bezel and adjusted the needles to zero. They where both below the lines Next I found the smaller of the two 2 Meg meter resistors was reading 7.5meg!? ?I replaced it and now the meter reads correctly. I used my fluke HV probe to find 2050 volts low and 2950 volts high.? I also found screen at 320 low and 426 high.? My line voltage is 126 today. The PS had been recapped but the can cap and the screen cap where factory.? I replaced the screen with a new 20mfd 500 volt sprauge.? I don't have the can cap.? I do have a 30/30 at 450 volt FT cap.? It's very high quality.? I have reservations about running 426 volts on a 450 cap though.? Maybe I get look at the data sheet.? Otherwise I will have to order 500volt caps. |
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Re: SR2000 and P2000 restoration continues
AFAIK, withstanding voltage has little to no affect on capacitance.? Capacitance is plate area vs dielectric thickness.? I have seen capacitors test within their capacitance tolerance but fail for withstanding voltage way below the rated value. If the dielectric reforms to a lower withstanding voltage, would not the dielectric be thinner?? A thinner dielectric would indicate a higher capacitance, would it not? Regards, Jim Logic: Method used to arrive at the wrong conclusion, with confidence.? Murphy
On Saturday, May 4, 2024 at 12:47:32 PM CDT, W7WRX <clark@...> wrote:
Good point
This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it
on a terminal strip. The can cap is dated 1967.??
These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time.
C
C
On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote:
One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec.
A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance.
Walt Cates, WD0GOF
?
A majority of acceptance is not proof of correctness.
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:01 PM To: [email protected] <[email protected]> Subject: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
The high voltage meter was reading way low.? I took the supply apart. Cleaned it, removed the meter bezel and adjusted the needles to zero. They where both below the lines Next I found the smaller of the two 2 Meg meter resistors was reading 7.5meg!? ?I replaced it and now the meter reads correctly. I used my fluke HV probe to find 2050 volts low and 2950 volts high.? I also found screen at 320 low and 426 high.? My line voltage is 126 today. The PS had been recapped but the can cap and the screen cap where factory.? I replaced the screen with a new 20mfd 500 volt sprauge.? I don't have the can cap.? I do have a 30/30 at 450 volt FT cap.? It's very high quality.? I have reservations about running 426 volts on a 450 cap though.? Maybe I get look at the data sheet.? Otherwise I will have to order 500volt caps. |
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Re: SR2000 and P2000 restoration continues
开云体育
I had a good cabinet scanned and here is what they came up with.?
I used a HVLP gun to apply, but did not try to duplicate the "blotch texture".
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 1:26 PM To: [email protected] <[email protected]> Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
Walt. Do you happen to have a paint code or suggested pain for the cabinets?? I placed the PS cabinet in warm water and Dawn soap for a soak. I came back to see the paint all peeling off.??
It looks like someone painted over the factory paint with a latex paint. I can see the factory paint under it.
I will need to strip both cabinets and paint.? Considering powder coat also.
C
From: [email protected] <[email protected]> on behalf of waltcates via groups.io <cateswa@...>
Sent: Saturday, May 4, 2024 11:22 AM To: [email protected] <[email protected]> Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The only time my 2000 is run on High is a couple times a year I tune up just to test the condition of the tubes?.
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:47 PM To: [email protected] <[email protected]> Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
Good point
This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it
on a terminal strip. The can cap is dated 1967.??
These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time.
C
C
On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote:
One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec.
A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance.
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:01 PM To: [email protected] <[email protected]> Subject: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
The high voltage meter was reading way low.? I took the supply apart. Cleaned it, removed the meter bezel and adjusted the needles to zero. They where both below the lines Next I found the smaller of the two 2 Meg meter resistors was reading 7.5meg!? ?I replaced it and now the meter reads correctly. I used my fluke HV probe to find 2050 volts low and 2950 volts high.? I also found screen at 320 low and 426 high.? My line voltage is 126 today. The PS had been recapped but the can cap and the screen cap where factory.? I replaced the screen with a new 20mfd 500 volt sprauge.? I don't have the can cap.? I do have a 30/30 at 450 volt FT cap.? It's very high quality.? I have reservations about running 426 volts on a 450 cap though.? Maybe I get look at the data sheet.? Otherwise I will have to order 500volt caps. |
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Re: SR2000 and P2000 restoration continues
开云体育
The only time my 2000 is run on High is a couple times a year I tune up just to test the condition of the tubes?.
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:47 PM To: [email protected] <[email protected]> Subject: Re: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
Good point
This particular Dual section FT Germany cap is rated at 450 working voltage for 34,000 hours.? It states your allowed 500 volts 5 x a minute.? I think that is the standard greater than 315 volt x 1.1 spec for surge. I think I will install it
on a terminal strip. The can cap is dated 1967.??
These are floating voltages.? When keyed these of course all drop down.? I wouldn't let the rig sit on high for long periods of time anyways.? I run it on low 99 percent of the time.
C
C
On May 4, 2024 10:22 AM, "waltcates via groups.io" <cateswa@...> wrote:
One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec.
A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance.
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:01 PM To: [email protected] <[email protected]> Subject: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
The high voltage meter was reading way low.? I took the supply apart. Cleaned it, removed the meter bezel and adjusted the needles to zero. They where both below the lines Next I found the smaller of the two 2 Meg meter resistors was reading 7.5meg!? ?I replaced it and now the meter reads correctly. I used my fluke HV probe to find 2050 volts low and 2950 volts high.? I also found screen at 320 low and 426 high.? My line voltage is 126 today. The PS had been recapped but the can cap and the screen cap where factory.? I replaced the screen with a new 20mfd 500 volt sprauge.? I don't have the can cap.? I do have a 30/30 at 450 volt FT cap.? It's very high quality.? I have reservations about running 426 volts on a 450 cap though.? Maybe I get look at the data sheet.? Otherwise I will have to order 500volt caps. |
|
Re: SR2000 and P2000 restoration continues
开云体育
One thing to remember about electrolytic capacitors; A capacitor rated at Xuf at Yvolts means that at at Yvolts it will react as a X value capacitor. The max voltage on the capacitor is another spec.
A capacitor that is run at less than its specified voltage will reform at the lower voltage and yield less capacitance.
Walt Cates, WD0GOF
?
From: [email protected] <[email protected]> on behalf of W7WRX <clark@...>
Sent: Saturday, May 4, 2024 12:01 PM To: [email protected] <[email protected]> Subject: [HallicraftersRadios] SR2000 and P2000 restoration continues ?
The SR2000 is working great now with thr offset fox in place.? ?Today was time to go through the P2000
The high voltage meter was reading way low.? I took the supply apart. Cleaned it, removed the meter bezel and adjusted the needles to zero. They where both below the lines Next I found the smaller of the two 2 Meg meter resistors was reading 7.5meg!? ?I replaced it and now the meter reads correctly. I used my fluke HV probe to find 2050 volts low and 2950 volts high.? I also found screen at 320 low and 426 high.? My line voltage is 126 today. The PS had been recapped but the can cap and the screen cap where factory.? I replaced the screen with a new 20mfd 500 volt sprauge.? I don't have the can cap.? I do have a 30/30 at 450 volt FT cap.? It's very high quality.? I have reservations about running 426 volts on a 450 cap though.? Maybe I get look at the data sheet.? Otherwise I will have to order 500volt caps. |
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Re: Sprague capacitors variants
开云体育Wekemp ?, yes I have that stored away , but my page nos seem to be a different format ? One of the very few ads for clorinol caps, and it says it is Askeral too ?? pdf??? 12? -----??????? ?? my computer refuses to do single line spacing now. ? From: [email protected] [mailto:[email protected]] On Behalf Of wekemp@...
Sent: Friday, May 3, 2024 8:39 PM To: [email protected] Subject: Re: [HallicraftersRadios] Sprague capacitors variants ? I have been examining the US EPA documents about PCB oil used in condensers. Sprague is stated to have used a PCB oil with trade name Clorinol, Cornell Dubiler used Dykanol, Aerovox used Hyvol, and Sangamo used Diaclor. This is from Table 4-3 on page 4-11 (Image 67 of 346) of . The only type of condenser produced by Spraque which contained Clorinol that I could find were AC condensers used as motor run/start capacitors. Curiously at least two of this type of capacitor are still available for sale on EBay (for example Sprague OVD-4300 30 MF 440 VAC). One of the comments from which I found particularly interesting was: “Worked at Sprague electric in Vermont as a designer in R and D. The Black Beauty went through many iterations, i.e. dielectrics, insulators, encapsulation material. While they look the same their properties are quite different, and their construction; i.e., winding of the foils, the mandrill size, and tension foils overlays dielectric thicknesses, all made up the voltage and capacitance and frequency ratings the encapsulation material effects. Most were made to customer orders and specifications while there’s some (which were) generic their specifications were very broad.” So Sprague Black Beauty capacitors were a trade name for a variety of tubular film capacitor types of varying electrical and material properties that evolved over their life time. ? -- don??? va3drl |
Floyd - K8AC
Jim Whartenby
don Root
waltcates