Questions about some tubes I received from a long time friend. - Page 1
Forum section: electronics / beginners

author: dzarren
author_rank: Contributor
timestamp: March 27, 2018, 08:41:44 am
content: I got these tubes from a friend, but i don't really know what they are, he has given them to me because he knows i like this type of technology. I looked up a few of these tubes, and some of them seem quite expensive, others not so much, could you please tell me more about these? A few I have tend to come in matched pairs online, i dont have pairs, does that make them useless?Could you please tell me what any of these tubes do if you know? I just started getting into restoration of 30's-60's stuff, so i'm looking to learn and maybe make use of this stuff for a restoration.JAN-CYN-4E27Hytron VT 104Marconi 5R4GYRogers 5R4GYCatham JAN-CAHG-5R4WGAMarconi 6AS7G

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 27, 2018, 09:30:57 am
content: Read 'til your heart's content:http://www.mif.pg.gda.pl/homepages/frank/Tim

author: KD4PBS
author_rank: Contributor
timestamp: March 27, 2018, 08:27:41 pm
content: The 5R4 tubes are mostly useless, unless you're looking to utilize them in equipment that uses them. They are rectifier tubes, and can easily be replaced for much less money, more reliability, and higher power handling with semiconductor diodes if creating a new circuit.The VT104 would make a nice small HF final amplifier or a low power class A audio amplifier if you were to build one. Other uses, again, would be a replacement tube for equipment using the same tube.The 4E27 can be used in a decently powered amplifier, but the design of the tube is likely to be one of relatively low mu, and would require quite a bunch of drive, so it wouldn't be wise at all to spend much time and money designing an amplifier (audio or RF) that would use them. At least you have a pair, and you could run them push-pull or make a lower power class A audio amp with them.It looks like you also have an 813 in the lot. That would make a nice AF or HF amplifier, and the venerable 807 is more or less a baby 813, and is used in lots of amateur radio and audio stuff up until they stopped making much of the equipment for vacuum tubes.That is assuming they all have good emission.And as far as using them to restore older equipment, it's unlikely that you'll find much consumer grade stuff that uses any of those tubes you have in the box.A more popular thing to do with them nowadays, and probably more practical, is to turn them into table lamps or displays by just lighting the filaments and letting them warm your room in the summer

author: byoungblood
author_rank: Contributor
timestamp: March 27, 2018, 10:35:33 pm
content: There are plenty of people out there still using those rectifier tubes either in old equipment that takes them, or in new builds to get the "tube sag" sound.What are some of the other tubes in the background there? I see you're in Canada, so the shipping may not make sense, but I'd be interested in seeing if there's anything usable there.

author: dzarren
author_rank: Contributor
timestamp: March 28, 2018, 02:50:07 am
content: Thanks!Here is a full list.Already listedLewis Electric JAN-CYN-4E27Hytron VT 104Marconi 5R4GYRogers 5R4GYCatham JAN-CAHG-5R4WGAMarconi 6AS7GOthers;Westinghouse 813Sylvania 807 B5GE 6080RCA 7-39GE 6BX7 GTRogers 45-62Westinghouse JAN-CK-0D3Mullard EF55Westinghouse 6AC7GE 6AC7 1852Rogers 6CB6GE 6J6ARogers 6CL6Sylvania 6CL6Philips 85A2Marconi 6AH6Unknown brand 6DJ8Siemens 85A2

author: Rog520
author_rank: Regular Contributor
timestamp: March 28, 2018, 03:12:24 am
content: If you're talking resale value, the 5R4GY, 6AS7G, 813, and 807 are all sought after by the tube audio guys. 807 is being used as a sub for the 6L6 with an adapter. NOS is obviously more valuable than used. The rest of them aren't worth much.