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Old 25th February 2009, 11:18 PM   #101
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- The 10M45 looks like it was installed OK.

- Did you line up the tube sockets such that the notch in the hole aligns with the notch on the silkscreen? Geoerge has a picture of this here:

Click the image to open in full size.


Quote:
Originally posted by nikolas812
Can you explain to me how to do this as if you were telling a 5 year old?
Put your meter in the ohms setting. Touch the leads together and it should read very close to 0 ohms.

Now, measure between T1-RED-YEL and the side of R4 closest to the edge of the board? What is the resistance in ohms?

Also, what is the rating of the fuse? How many amps, fast or slow blow?
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Old 25th February 2009, 11:37 PM   #102
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Quote:
Originally posted by korneluk
- The 10M45 looks like it was installed OK.

- Did you line up the tube sockets such that the notch in the hole aligns with the notch on the silkscreen? Geoerge has a picture of this here:

Click the image to open in full size.




Put your meter in the ohms setting. Touch the leads together and it should read very close to 0 ohms.

Now, measure between T1-RED-YEL and the side of R4 closest to the edge of the board? What is the resistance in ohms?

Also, what is the rating of the fuse? How many amps, fast or slow blow?

Yes the tube sockets were lined up correctly

Where do you put the red probe and the black probe? Does it matter. I get different reading each way. Neither stay the same. They change the longer I hold the probes on..


With the red probe touching T1- red yellow and the black the probe touching R4 closest to the edge it reads. Well. SOmething different every time. The last time read 2.512m some times it read 1.9 sometimes it reads 39.2 and it changes the longer you hold them on there..



I also have fast blo fuses. 1.6a and 2.5a

I have only used the 1.6a so far...


Nick
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Old 25th February 2009, 11:48 PM   #103
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Quote:
Originally posted by nikolas812

I also have fast blo fuses. 1.6a and 2.5a

I have only used the 1.6a so far...
Ooops! The KT-88 tubes you're using consume 1.6A each on the heaters alone, plus 2A for the 5AR4 rectifier heaters, plus .3A for the 12AT7, plus the B+ current draw.

You better get some 5A slow blow fuses and try again...
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Old 25th February 2009, 11:52 PM   #104
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OK.

Got some.



Here goes nothing....



Nick
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Old 25th February 2009, 11:57 PM   #105
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Blew it.


the 12at and 5ar4 started to light up then 5ar4 start flickering with blue and the fuse blew...




Nick
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Old 26th February 2009, 12:02 AM   #106
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Quote:
Originally posted by nikolas812
...then 5ar4 start flickering with blue and the fuse blew...
Blue flickering means arcing due to excessive current draw.

Can you please check that capacitors C1 and C2 are installed with the right polarity - i.e. the (-) negative side to ground?
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Old 26th February 2009, 12:04 AM   #107
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There right.





Nick
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Old 26th February 2009, 12:18 AM   #108
chrish is online now chrish  Australia
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Quote:
Originally posted by korneluk


Ooops! The KT-88 tubes you're using consume 1.6A each on the heaters alone, plus 2A for the 5AR4 rectifier heaters, plus .3A for the 12AT7, plus the B+ current draw.

You better get some 5A slow blow fuses and try again...
THIS IS NOT GOOD ADVICE!!!!!

In a transformer, incoming power is equal to outgoing power (in an ideal transformer).

Power = Volts x Amps

Therefore Volts x Amps in = Volts x Amps out.

Your transformer is rated for something like 120 volts in, 750 volts out at 200mA, 6.3 volts out at 6A and 5.0 volts out at 3A.

750 volts at .2A = 1.25 Amps at the input
6.3 volts at 6A = 0.315 Amps at the input
5.0 volts at 3A = 0.125 Amps at the input

TOTAL = 1.69 Amps.

You should use a 2 or 2.5 Amp SLOW BLOW fuse.

Chris
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Old 26th February 2009, 12:19 AM   #109
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Nick,

Disconnect the auxiliary motor run cap and try again.
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Old 26th February 2009, 12:21 AM   #110
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Quote:
Originally posted by chrish


THIS IS NOT GOOD ADVICE!!!!!

In a transformer, incoming power is equal to outgoing power (in an ideal transformer).

Power = Volts x Amps

Therefore Volts x Amps in = Volts x Amps out.

Your transformer is rated for something like 120 volts in, 750 volts out at 200mA, 6.3 volts out at 6A and 5.0 volts out at 3A.

750 volts at .2A = 1.25 Amps at the input
6.3 volts at 6A = 0.315 Amps at the input
5.0 volts at 3A = 0.125 Amps at the input

TOTAL = 1.69 Amps.

You should use a 2 or 2.5 Amp SLOW BLOW fuse.

Chris
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