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Forum 141

Bottle ID

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Refugee
(@refugee)
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I had a little fiddle with an ultrasonic cleaner i have had since the 1970s.
I made a mistake when i wrote the number back on the valve.
I used magic marker and when i was using it to sort out a jammed car door lock in the 1980s that took all day the writing burned off the valve :(
It looks like a pentode or perhaps a beam tetrode of a transmitting or line output type and will be blasting away at a pretty high voltage in order to drive the huge polo mint shaped piezo transducer.
I powered it up and it went like it always has done :thumbl:

 
Posted : 08/10/2012 12:58 am
sideband
(@sideband)
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An EL or PL36 perhaps depending on the heater voltage? Looks about right for one of those.

Rich

 
Posted : 08/10/2012 9:33 am
Refugee
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It is about the same size as a PL509 however it is on an octal base.
So it is a bit more powerful than a PL36.
I would say from the size and weight that the transformer is about 300 - 400 VA.
I will have to find a way of measuring the heater safely as the anode voltage looks pretty high.
I will have to put it on the variac and do it at 24vac input.
There is a getter just spot welded onto the anode and the marking on the glass can be seen in the third photo.
I will have to do it in the daylight though.
The G3 looks like an inner anode with circular cutouts that can be seen through the square cutouts in the anode.
I had a look at the 813 and came to the conclusion that it is not the same as it is directly heated and my beast is indirectly heated and has a warm up time that is consistent with this.
I put the close up photo on while i was looking into the heater and grid count.

 
Posted : 08/10/2012 12:40 pm
GlowingAnode
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6GW6?
See here; http://tubedata.milbert.com/images/RCA/ ... RCA_EF.jpg

Rob.

Thursday night is shed night.

 
Posted : 08/10/2012 1:15 pm
Refugee
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That is the one.
I looked on the UK valve museum site and they had nothing starting 6D and i did have the first two digits of the number remaining.
I thought it showed some common looks to a line output valve.
It is going to be a pain to get a replacement as the audiophools are at it.
The one i have got is working well :thumbl:
6DQ6B/6GW6 looks right.
that is a very useful web link.
Cheers :thumbl:

 
Posted : 08/10/2012 1:39 pm
GlowingAnode
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The G3 looks like an inner anode with circular cutouts that can be seen through the square cutouts in the anode.

These are the beam deflection plates, as this is a beam tetrode not a pentode.

I had a look at the 813 and came to the conclusion that it is not the same as it is directly heated and my beast is indirectly heated and has a warm up time that is consistent with this.

The 813 is a very different beast, much larger and graphite anode.
Rob.

Thursday night is shed night.

 
Posted : 08/10/2012 3:39 pm
Refugee
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I was thinking of a beam tetrode being most likely to start with and that looks indeed like what we have got.
I have now had a look at the rating plate and model and it looks like 100W of power.
The valve is just over an inch and a half wide so it is big enough to handle the power.
The mains rating is 125W and there is about 10W for the heater and 5W for the fan.
The transformer looks a bit large as it has to be de-rated a bit as the valve is running in half wave due to a rectifier not being present.

 
Posted : 08/10/2012 6:32 pm
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