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#1
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1N1239 Solid State replacement for 5R4 tube
Can anyone tell me exactly what these replacement plugs have in them and a schmatic so I can make some for myself I have the plugs to use but need the rest of the info to bulid them. Thanks Wayne AA5JJ please reply to --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.524 / Virus Database: 321 - Release Date: 10/6/03 |
#2
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![]() "AA5JJ" wrote 1N1239 Solid State replacement for 5R4 tube Can anyone tell me exactly what these replacement plugs have in them and a schmatic so I can make some for myself I have the plugs to use but need the rest of the info to bulid them. ****Wayne,your nominated reply email address is invalid,hence the reply here. There are two 1N4007 silicon diodes in an Octal base.Pin 4 is diode 1 Anode,pin 6 is diode 2 Anode and the two cathodes connect to pin 8.You will probably have to include a power resistor of about 47 Ohms @ 10 Watts to drop the output voltage to the same value as would have been provided by the vacuum tube rectifier. Cheers from down under,Brian Goldsmith. |
#3
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![]() "AA5JJ" wrote 1N1239 Solid State replacement for 5R4 tube Can anyone tell me exactly what these replacement plugs have in them and a schmatic so I can make some for myself I have the plugs to use but need the rest of the info to bulid them. ****Wayne,your nominated reply email address is invalid,hence the reply here. There are two 1N4007 silicon diodes in an Octal base.Pin 4 is diode 1 Anode,pin 6 is diode 2 Anode and the two cathodes connect to pin 8.You will probably have to include a power resistor of about 47 Ohms @ 10 Watts to drop the output voltage to the same value as would have been provided by the vacuum tube rectifier. Cheers from down under,Brian Goldsmith. |
#4
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Brian Goldsmith wrote:
There are two 1N4007 silicon diodes in an Octal base.Pin 4 is diode 1 Anode,pin 6 is diode 2 Anode and the two cathodes connect to pin 8.You will probably have to include a power resistor of about 47 Ohms @ 10 Watts to drop the output voltage to the same value as would have been provided by the vacuum tube rectifier. Cheers from down under,Brian Goldsmith. Voltage drop for a 5R4 is on the order of 67 volts at 250ma. A 47 ohm resistor will only drop 12 volts in this example. -Bill |
#5
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Brian Goldsmith wrote:
There are two 1N4007 silicon diodes in an Octal base.Pin 4 is diode 1 Anode,pin 6 is diode 2 Anode and the two cathodes connect to pin 8.You will probably have to include a power resistor of about 47 Ohms @ 10 Watts to drop the output voltage to the same value as would have been provided by the vacuum tube rectifier. Cheers from down under,Brian Goldsmith. Voltage drop for a 5R4 is on the order of 67 volts at 250ma. A 47 ohm resistor will only drop 12 volts in this example. -Bill |
#6
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![]() A 5R4GYB is rated at 3100V PRV. You would need 3 1N4007's in series in each leg (total of 6) to match the peak reverse voltage rating. I have solid-stated the 5R4 in a Hallicrafters HT32B without using a series resistor to drop the HV back down to that produced by the 5R4. That's OK in this application, because the 5R4 is only used for the plate supply for the 6146's. Using the higher plate voltage, I just readjusted the grid bias for the same 40 mA resting current. 73, Ed K4PF |
#7
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![]() A 5R4GYB is rated at 3100V PRV. You would need 3 1N4007's in series in each leg (total of 6) to match the peak reverse voltage rating. I have solid-stated the 5R4 in a Hallicrafters HT32B without using a series resistor to drop the HV back down to that produced by the 5R4. That's OK in this application, because the 5R4 is only used for the plate supply for the 6146's. Using the higher plate voltage, I just readjusted the grid bias for the same 40 mA resting current. 73, Ed K4PF |
#8
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![]() "Edward Knobloch" wrote A 5R4GYB is rated at 3100V PRV. You would need 3 1N4007's in series in each leg (total of 6) to match the peak reverse voltage rating. *** You are correct,however the original poster stated he wanted a replacement for a 5R4.This tube has a maximum plate Voltage of 750 RMS per plate for which a 1N4007 will suffice. Brian Goldsmith. |
#9
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![]() "Edward Knobloch" wrote A 5R4GYB is rated at 3100V PRV. You would need 3 1N4007's in series in each leg (total of 6) to match the peak reverse voltage rating. *** You are correct,however the original poster stated he wanted a replacement for a 5R4.This tube has a maximum plate Voltage of 750 RMS per plate for which a 1N4007 will suffice. Brian Goldsmith. |
#10
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![]() Brian Goldsmith wrote: snip however the original poster stated he wanted a replacement for a 5R4.This tube has a maximum plate Voltage of 750 RMS per plate for which a 1N4007 will suffice. The 5R4 has a maximum piv voltage of 2800 volts, so you would still need 3 1N4007's in series in each leg for equivalent safety factor. The rated max supply voltage of 750V rms per plate means that you should not use a transformer higher than 1500V rms center tapped in a full wave single phase rectifier circuit using a 5R4. The designers expected switching transients when the current is interrupted in the HV transformer and HV choke, and therefore included a max supply voltage for guidance. 73, Ed K4PF |