Good-day again to those who have so (very) patiently waited for my responses to their questions concerning radio valve information. As some of you may realise, I have been very busy organising other aspects of my life recently and for that reason I have not had time to devote to some of your valve questions for quite a time. So here goes with the latest batch.
(You can view even earlier questions-and-answers by using this link if you wish to refer to them. Not all of the data in these question-and-answer pages are yet incorporated into the main valve data page).
First of all, another tip as to where to (possibly) obtain valves/tubes and other old bits and pieces - someone in Australia has apparently collected much material over the years and wrote:
"As I hate sending perfectly good gear to the rubbish tip, over the years I have gathered some valves and old bits and pieces which I would like to make available to those who can put it to good use ... hence there is a section of our site listing this stuff."The Web address he gave me for this was at http://www1.tpgi.com.au/users/hadrecs/VintageData00.html (this link, thus) and might well be worth looking at.
Nils Hornfalk (nils.hornfalk@seind.mail.abb.com) recently bought a valve amplifier called a PAM-Samson. He says it has a 5Z3, a 6Y7G octal, and a 6J7 metal octal plus a 42 (or 6F6). He also asks for data on the ECLL800 valve as well. Well the 5Z3 is a full-wave rectifier tube, base UX4, with the following pinout:
5Z3:- 1:f 2:a" 3:a' 4:f Vf=5volts, If=3.0amp, Va(rms)=450, Ia=670mA.The 6Y7G data I don't have to hand at this moment, but it would also seem to be a rectifier and I wonder why there would be two rectifier tubes in such an amplifier....
The 6J7 is actually an R.F. pentode, octal base, indirectly-heated. With the exception of the metallization and encapsulation, the 6J7, 6J7G and 6J7GT are electrically and pinout-wise identical, and as follows:
6J7:- 1:s 2:h 3:a 4:g2 5:g3 7:h 8:k TC=g1 Vh=6.3V Ih=0.3A Va=250 Vg2=100
Vg1= -3 Gm=1.25mA/V.
The 6F6 is an audio output pentode, equivalent to the KT63, and has an anode dissipation rating of 11 watts. Anode impedance is around 80Kohm, but with an optimum load of 7Kohm audio primary. The pinout is as follows:-
6F6:- 2:h 3:a 4:g2 5:g1 7:h 8:k/g3 Va=285 Ia=38mA Vg1= -20 Vg2=250
and is usually operated with a cathode bias resistor of some 390 - 470 ohms.
As for the ECLL800, this is a triode+double-output-pentode valve, usually used in circuits where the triode serves as a phase-splitter to drive the two associated pentodes in 'push-pull' - please also look at the replies quoted below this paragraph.. I can find no quoted equivalents for this valve, which is of European origin. From memory, I would treat it as an ECL82 with an extra pentode in the same envelope, but look at the base connections to the valve electrode connections to establish the pin-out, it must have a common cathode for all 3 valve functions, with the input signal being fed to g1 of the triode and g1 of the first pentode (using a common connection), the anode of the triode supplying output via a capacitor and bias resistor to g1 of the second pentode (in anti-phase), g2 of both pentodes being common, and g3 of both pentodes being bonded to cathode. With 2 more connections for heaters you have a complete 9-pin set when you include the two output-pentode anode connections to the push-pull output transformer. Please note that I will ascertain the actual connections during the next couple of weeks before you might use this information. If anyone else has information on this valve in advance of my searching, please e-mail me at tgale@xs4all.nl under this link and I would appreciate the effort.
In fact, and very quickly indeed, I have had a response about some of these tubes and I include it here with grateful thanks to the sender. Here it is (Thank you, Douglas Dawson - dawsondc@postoffice.worldnet.att.net :-
From: Douglas Dawson Jun 4, 1998 11:30 Here is some information on US tube types which you mentioned in your most recent missive. 1. US type 6Y7G is a dual power triode intended for zero-bias, Class B service. It is equivalent, except for the octal base, to US type 79. Pinout, in your nomenclature, is: 1:s 2:h 3:a" 4:g" 5:g' 6:a' 7:h 8:k In the amplifier mentioned, the 6Y7G is probably the final power amplifier, driven by the 6F6 in triode connection. 2. Type 6SS7 is a remote-cutoff (variable mu) RF pentode, electrically equivalent to loctal type 7B7. The closest equivalent is probably type 6SK7 (equiv: 7A7) which is also a remote-cutoff type and has the same base and pinout. Heater current for the 6SK7 is 0.3 amperes instead of 0.15 for the 6SS7. Transconductance for the 6SK7 is slightly higher and anode resistance slightly lower. 3. I, too, cannot find anything on a type 952. Most of the 95_ series are "acorn" style tubes which are not likely to be found in a consumer product as they were mostly used for the military or industrial application. 4. Most of the US types mentioned are readily available by mail order in the US for around 5 USD. Here are two URL's for US businesses supplying tubes:
I have also had a response regarding the ECL800 valve, and I quote some of this with thanks to Scott Robinson under the subject: Tube 6KH8/ECLL800 Pinout?
-I wondered the same thing when first I encountered this tube. It's like -this(I have edited the pinout format - FCTG):- -1:a 2:gt and g1 of Pentode-1 3:a'p 4:h 5:h 6:g1(Pentode-2) 7:k(common) -8:a"p 9:g2(both pentodes)
-Whew! Useful item, pity they are so expen$ive...Thanks again, Scott.
Next, Anne Forbes (dragonette@geocities.com) tells me that she would like
help regarding a Philips 'radioplayer' model 177. She would like to know
how old this apparatus is and something about replacement valves if and when it
breaks down. She has the instruction booklets but no date of manufacture, etc.
Well, Anne, you may already know that the Philips organisation is based
right here in The Netherlands (Holland to many) in the city of Eindhoven,
although they have many other plants over the world. I have the 'radio-vademecum'
(a fairly complete listing of old Philips (and other) radio and record-player
models of the type, and this shows me models such as the 707A, the 707U,
the 709A, the 710A and so forth which are all radio-gramophones - but I
have not found reference to the 177 model you quote. All the others I just
mentioned were from the years 1940-41; however the model you have may well
be an export model not catalogued in this reference.
In general, I would recommend that (a) you examine the valves to ascertain
their type numbers, and then refer to my (or other's) valve data pages
to find out replacement data if and when required, and (b) look at the
cylindrical 'capacitors' (or, 'condensers' as they were then called) which
probably have values on them such as '16uF' or '8 mmf' or '25micro-F'
stamped on them - they often also have their production date written on them
as well, which gives an idea as to the age of the set.
Again, I promise to look further to see if I can find an absolute reference
to the model you seem to have - perhaps you could e-mail me with the
details of any labels or information you can see on the rear of the set.
This would help me in further identification of the model.
Next, I was asked about the transmitting tube used in many amateur radio
sets commercially manufactured (such as the KW2000A from KW Electronics)
which is the 6146 and it's variants...
Well, the 6146 has often been used, usually in pairs, in many of such sets,
and is described in the R.S.G.B. (Radio Society of Great Britain) publication
'Radio Communication Handbook' and is also mentioned in the ARRL Handbook
from the equivalent American society.
The 6146 has the following pinout:-
6146:- 1:k/bp 2:h 3:g2 4:k/bp 5:g1 6:k/bp 7:h 8:base-sleeve TC=anode.
I continue to receive requests for obtaining or purchasing components and in this respect Ken Crum (Cadd55Ken@aol.com) asks me how to obtain two PX25 valves for his Decca DECOLA which he is restoring. I am sorry to have to repeat this, but I am not in any way involved in the sourcing or selling of tubes/valves or any other components but I understand that in many places it is difficult to find out where/how to get spares for our hobby. I can only recommend some of the site(s) that I have noted in these pages, and by all means would anyone who can help please E-mail me or the person in question if they have an idea where such purchases may be made - but please do not ask me for components for sale.
randrend@euronet.nl enquired about the EL34 pentode valve. This is an
audio output pentode, sometimes used in push-pull using a pair of them,
and is equivalent to 6CA7 and KT77. The heaters are 6.3V, 1.5A. Used in
single-ended class-A, the ratings are: Va=250V, Vg2=250V, Vg1= -12.2V,
Ia=100mA, Ig2=15mA, Ra=15Kohms, gm=11mA/V; this with a cathode resistor
recommended as 100 ohms, an anode load of 2Kohms and giving Pout of 11 watts.
Used in push-pull, the ratings are: Va=375V, Vg2=275V, Vg1=-33V, Ia=110mA,
Ig2=23mA, anode-to-anode load = 3.5Kohms, giving a power output of 40 Watts.
The pinout is as follows:
1:g3 2:h 3:a 4:g2 5:g1 6:NC 7:h 8:k
Gary Harris (gwharris@primenet.com) is restoring a Hammarlund HQ-129-X receiver, and looking for 6SS7 (r.f. / i.f. amplifier valves) and 6K8 (l.o/mixer valve). The 6K8 is categorised as follows:-
6K8G TRI-HEXODE OCTAL 6.3V 2:h 3:ah 4:g2/4 5:g1 6:at 7:h 8:k TC=g3
Va=250V Vg1=-3V equivalent to WTT128.
The 6SS7 is something more of a mystery and I am wondering if this could
possibly be substituted by something like a 6SG7 (vari-mu R.F. pentode) or
a 6SH7 (straight R.F. pentode) - both these have the same pinout as the
6SS7 except
that pins 3 and 5 are connected together as a common k/g3 connection.
The pinout for the 6SS7 was as follows:-
1:s 2:h 3:g3 4:g1 5:k 6:g2 7:h 8:aFrom the type number I would assume it has a 6 or 6.3-volt heater, like the 6K8 has.
CHAROBS@aol.com enquires about a tube type 952 in a Magnavox radio/turntable some 50 years old. I cannot find anywhere a reference to that number, but the function is more or less certain to be that of an amplifying triode. There are two apparently similar triodes with this type of base, the 955 and the 957 / 958. The 957 and 958 are directly-heated filament-cathode triodes with the following pinout:
957 / 958:- 1:f+ 2:a 3:g 4:f- 5:f(ct) - used as cathode connection.
955:- 1:h 2:a 3:g 4:h 5:k
Jukka Rahikainen (jukka.rahikainen@icl.fi) is examing the Telefunken set he has on his hands containg an AL41 output pentode, an ABC1 double-diode-triode, and an AZ1 rectifier valve - and asks about the pin-outs for these valves. Well, Jukka, the 'A' prefix to these type numbers implies that they are 4-volt heater types as you mention. The AZ1 is a 4-volt version of the EZ1, for about 30mA rectified current. The pin-out would appear to be as follows (from my AVO test-meter book):-
AZ1: 1:NC 2:f- 3:f+ 4:NC 5:a' 6:NC 7:NC 8:a"The ABC1 valve, from the same source, would appear to be as follows:-
ABC1: 1:NC 2:f- 3:f+ 4:k 5:a"diode 6:a'diode 7:NC 8:a(triode) TC=g1.
Va=250V, Vg1= -7V, Ia=4mA, gm=2mA/V.
Unfortunately, the AL41 seems to evade my sight at the moment, but I
would bet that it could be similar to the UL41 but with the 4-V heaters.
Jim Tiano (james.tiano@exgate.tek.com) has sent me a request concerning the characteristic curves for the 76 valve. The 76 was a general-purpose triode, with the pinout as follows:-
76: 1:h 2:a 3:g 4:k 5:h
Vh=6.3V Ih=0.3A; and you can select from two sets of data I present here:
Va Ia Vg1 Ra Gm
(a) 100V 2.5mA -5V 12Kohm 1.15mA/V
(b) 250V 5.0mA -13.5V 9.5Kohm 1.45mA/V
That's all for this time, thanks very much to those who have passed on comments on the valve radio page of mine, and here's to the restoration of our old-fangled devices with things inside where you *can* count the pins 8*) !
Best regards, 73's etc, F.C. Trevor Gale (you can e-mail me at tgale@xs4all.nl or by clicking here). Click here to go back to the Old Radio Valves/Tubes main page. As mentioned, not all the latest info is incorporated into the data page yet. Happy restoring and listening!