I think it's a 5AR4, but could be wrong The plates and double D top getters look like an old Mullard but it doesn't have a hole in the bottom of the base pin nor the etched date code. I thought RCA did not manufacture 5AR4s before the early '70s. It's about the size of a '60s GE but no copper plate edges.
I know that just because it is marked "made in USA for EICO by RCA" doesn't necessarily mean that's true. I would believe the 58-52 date code though.
I'm stumped.
ID this Tube??
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David Root
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ID this Tube??
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Stevem
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Re: ID this Tube??
I do not think its a full wave recto like a 5ar4, 5y3 or 5v4 and such as the there seems to be only a single plate mass, I think its a half wave recto of some sort.
Get on the tube world site and scout around as they have good pictures of all the tubes.
Get on the tube world site and scout around as they have good pictures of all the tubes.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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David Root
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Re: ID this Tube??
Thanx for respnding, Stevem. My pics don't show the plate structure too clearly, I was focusing on the lettering on the base.
Here is another pic that to me looks a lot like a Mullard 5AR4. The flash is obscuring most of the space between the plates, but there are two plates with a support rod in between them.
Here is another pic that to me looks a lot like a Mullard 5AR4. The flash is obscuring most of the space between the plates, but there are two plates with a support rod in between them.
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Re: ID this Tube??
I have a Mullard logoed GZ34 that looks exactly like that: base bigger than glass and no hole in the guide pin. But mine does have an etched Blackburn code. I think Philips was pretty fussy about that. Are you sure there's no trace of a code? Maybe by the 70s they gave up on that for tubes made for other companies.
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David Root
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Re: ID this Tube??
Thanx Firestorm, that helps, I have also seen pics of old Mullards that had no base pin hole.
Mine is date coded last week of '58, (58-52) and I have a pair of '60 Mullard EL37s (B0J) that have no hole in the base pin either.
It looks like the so-called "fat base" Mullard except the upper mica is different. It has double D getters like the fat base Mullard.
But I can find no trace of a Philips etched code, or anything at all on the glass.
Mine is date coded last week of '58, (58-52) and I have a pair of '60 Mullard EL37s (B0J) that have no hole in the base pin either.
It looks like the so-called "fat base" Mullard except the upper mica is different. It has double D getters like the fat base Mullard.
But I can find no trace of a Philips etched code, or anything at all on the glass.
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Stevem
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Re: ID this Tube??
If that main plate structure mass is located in the dead center of the tube, its a half wave recto.
still hard to tell a 3 dimentional thing from 2 dimentional photo!
still hard to tell a 3 dimentional thing from 2 dimentional photo!
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
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Gibsonman63
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- Location: Texas
Re: ID this Tube??
I have read that if you put it in the freezer for a while, you will be able to see the outline of where the printing was when you pull it out. I have not tried this.
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martin manning
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Re: ID this Tube??
That has worked for me. Chill it, then breathe on the glass.Gibsonman63 wrote:I have read that if you put it in the freezer for a while, you will be able to see the outline of where the printing was when you pull it out. I have not tried this.
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David Root
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Re: ID this Tube??
Thanx for the freezer tip. I just tried it, but no joy. There is a small area that shows what look like scratch marks, but that is all.
Stevem, there are definitely two plate structures, separated about 1/8" in the center. In the middle of that space there is a stout support rod.
Stevem, there are definitely two plate structures, separated about 1/8" in the center. In the middle of that space there is a stout support rod.
Re: ID this Tube??
Sell it as cryogynically treated now for big bucksDavid Root wrote:Thanx for the freezer tip. I just tried it, but no joy. There is a small area that shows what look like scratch marks, but that is all.
Stevem, there are definitely two plate structures, separated about 1/8" in the center. In the middle of that space there is a stout support rod.
Re: ID this Tube??
Could it possibly be a Matsushita tube. They were set up by Mullard and I know that there EL34's look identical to a Mullard except for the guide pin hole. I see RCA branded tubes on Ebay quite frequently being sold as Mullards but are actually Matsushita tubes.
Re: ID this Tube??
Very possible I have some RCA jap '6ca7's Look exactly like mullards.Except for the base pin Good tubesdanman wrote:Could it possibly be a Matsushita tube. They were set up by Mullard and I know that there EL34's look identical to a Mullard except for the guide pin hole. I see RCA branded tubes on Ebay quite frequently being sold as Mullards but are actually Matsushita tubes.
Re: ID this Tube??
I agree cbass, very good tubes and the prices are still reasonable!
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David Root
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Re: ID this Tube??
Thanx again guys, maybe it is a Matsushita. Some Pics I've seen of those are not "fat base" types. Other ones that are "fat base" seem to have an "X" in the top of the glass, which mine doesn't have.
If it is a Matsushita then all the writing including the date code 58-52 is probably a fairy tale, as it seems the Matsushitas are from the '70s from what I can see from the web searches I've done. OTOH that would explain the lack of the etched Philips date code on my tube.
If it is a Matsushita then all the writing including the date code 58-52 is probably a fairy tale, as it seems the Matsushitas are from the '70s from what I can see from the web searches I've done. OTOH that would explain the lack of the etched Philips date code on my tube.