Why was there no PCC81/82/83?

[rock soderstrom]

I was asked yesterday why there was no PCC81/82/83?

Many well-known tubes such as the ECC88 or EF86 were also available as PCC88 or PF86 for series heating as used in TV sets.

I was irritated at first, because I had never thought about it before. After a little while, my answer was that the ECC 81/82/83 already offer a heating option of 300mA and are therefore compatible with the 300mA series heating of the P-tubes. In fact, the ECC81/82/83 are a kind of PCC81/82/83 with an additional 12.6 volt heating option. The EF86 and ECC88 have a different heater, they require more or less current than 300mA in parallel heating with 6.3V, which is why special P versions were needed.

Is everything correct or have I overlooked something?

 

[ruffrecords]

I don't recall ECC81/2/3 being used in valve TV sets. Most all of the were pentodes. The only time you might need the odd triode was in the AF chain where a single triode was most often combined with a pentode e.g. PCL82

http://www.r-type.org/exhib/aai0120.htm

Cheers

Ian

 

[moamps]

The only time you might need the odd triode was in the AF chain where a single triode was most often combined with a pentode e.g. PCL82..

PC(EC)86 and PC(EC)88 single triodes was used in TV tuners.

 

[rock soderstrom]

PC(EC)86 and PC(EC)88 single triodes was used in TV tuners.

PC(EC)92 triode was also used in televisions. (EC92 ~ half of a ECC81, was used in mics as well)

 

[rock soderstrom]

The only time you might need the odd triode was in the AF chain where a single triode was most often combined with a pentode e.g. PCL82

Sorry, that's not quite true, but the PCL82/ECL82 is a good-sounding low-watt tube!

Someone writes this on the Internet:"
The ECC 82 is mainly used in oscillator stages for picture deflection in televisions, the ECC 81 is often used in HF receivers (VHF/VHF) or tape recorders."

and Wikipedia says:

"ECC82 (AF amplifier, pulse separation stage in television receivers)"

It seems, that double ECC8x triodes were also used in televisions.

 

[kags]

PF86, PF83, and PC900 tubes are currently being used in mics and preamps…

 

[gyraf]

..ecc81, 82 and 83 are already 300mA tubes @6.3V - so they are "also" PCCxx

 

[C.B. - Boudio]

After a little while, my answer was that the ECC 81/82/83 already offer a heating option of 300mA and are therefore compatible with the 300mA series heating of the P-tubes. In fact, the ECC81/82/83 are a kind of PCC81/82/83 with an additional 12.6 volt heating option. The EF86 and ECC88 have a different heater, they require more or less current than 300mA in parallel heating with 6.3V, which is why special P versions were needed.

Is everything correct or have I overlooked something?

Yes, completely right.

 

[rock soderstrom]

..ecc81, 82 and 83 are already 300mA tubes @6.3V - so they are "also" PCCxx

Yes, completely right.

Thank you for the confirmation! I don't know if you know this feeling, but when I have a spontaneous realization, I often feel a little unsure whether what I've come up with is true or not.

The more I think about the subject, the more I suspect that the 300mA heater current of P-tubes was also chosen for a specific reason. Compatibility with existing E-tubes. Perplexity cites the EF184 as an example...I think the ECC8x also played a role.

 

[ruffrecords]

Sorry, that's not quite true, but the PCL82/ECL82 is a good-sounding low-watt tube!

Someone writes this on the Internet:"
The ECC 82 is mainly used in oscillator stages for picture deflection in televisions, the ECC 81 is often used in HF receivers (VHF/VHF) or tape recorders."

and Wikipedia says:

"ECC82 (AF amplifier, pulse separation stage in television receivers)"

It seems, that double ECC8x triodes were also used in televisions.

So, to answer your original question, ECC82 might have been used in a TV but not the ECC83 or ECC81.

Cheers

Ian

 

[rock soderstrom]

So, to answer your original question, ECC82 might have been used in a TV but not the ECC83 or ECC81.

Nope! please see the attached datasheet
ECC81 on Wikipedia:

"The 12AT7 has somewhat lower voltage gain than the 12AX7, but higher transconductance and plate current, which makes it suitable for high-frequency applications.

Originally the tube was intended for operation in VHF circuits, such as TV sets and FM tuners, as an oscillator/frequency converter, but it also found wide use in audio as a driver and phase-inverter in vacuum tube push–pull amplifier circuits.

This tube is essentially two 6AB4/EC92s in a single envelope. Unlike the situation with the 6C4 and 12AU7, both the 6AB4 and the 12AT7 are described by manufacturer's data sheets as R.F. (Radio Frequency) devices operating up to VHF frequencies.[1]"

 

[rock soderstrom]

Even the ECC83/12AX7 was used in TVs.

"in USA Zenith models "Brent, Mozart, Drew, Clark, Carroll, Archer" from 1953:
L1846E 'The Brent' Ch= 19L25 Television Zenith Radio Corp.;

all Emerson models 1956, e.g.:
1020H Ch= 120235-D Television Emerson Radio & Phonograph Cor

in England the Kolster-Brandes LFTxx models 1952:
LFT50 Television Kolster-Brandes Ltd. KB, ITT; Foots Cray; G

Bush, London, TV53 1955 (ECC83):
TV53 Television Bush Radio; London, build 1955, 2 pictures

in Italy models from Marelli 1954:
RV99 Television Marelli Radiomarelli; Sesto San Giovanni MI,

and some more, though all from the 1950's ... came out of fashion in the 60's ..."

from this thread:

https://www.diyaudio.com/community/threads/is-the-12ax7-ever-used-on-television-sets.286780/

 

[C.B. - Boudio]

Perplexity cites the EF184 as an example...I think the ECC8x also played a role.

P-heater valves predate the EF184, I think. But I'm quite sure the EF80 is an even better example. Those were used 'en masse' in many of those TV sets.

 

[rock soderstrom]

But I'm quite sure the EF80 is an even better example. Those were used 'en masse' in many of those TV sets.

+1. Very good example.

 

[rock soderstrom]

After all the talk about P-tubes, I really want to do something with them. Maybe a guitar amp with PF86 + PCL82/86?

I have enough OPTs for that


(Nine Grundig OPTs vs Hammond 125DSE and an Edcor XSM 10K/600 for size comparison.)

Or how about an RS124 style vari mu compressor with PCC189 valves? A REDD47 (now called PEDD47 ) with PF86 and a PCC88 would go well with that...

 

[C.B. - Boudio]

Or a larger (HiFi) amp with, for example, a couple of PL508s as power valves! You can easily get into EL34 territory with those, I think.
I use those P's because they're still really cheap ànd I've got a small NOS lot of them - no reason at all to use anything else!

 

[rock soderstrom]

Or a larger (HiFi) amp with, for example, a couple of PL508s as power valves! You can easily get into EL34 territory with those, I think.
I use those P's because they're still really cheap ànd I've got a small NOS lot of them - no reason at all to use anything else!

Not a bad idea either, a power amplifier. I actually just bought some PF508s and PF504s as bycatch.


Basically you can save a lot of money with P-tubes, PF86 for example you can get for cheap in a bundle with other tubes like the PL508 or PCL82. (and tons of tube diodes )

 

[rock soderstrom]

This diode, for example, is spooky, the imprint warns of X-rays!

No P-tube, but comes often with them...

 

[C.B. - Boudio]

Or something like the unbelievably useful DY87! ;-)

 

[C.B. - Boudio]

Basically you can save a lot of money with P-tubes, PF86 for example you can get for cheap in a bundle with other tubes like the PL508 or PCL82. (and tons of tube diodes )

Well, that's exactly what I'm doing, too!