Forums :: Resources :: Features :: Photo Gallery :: Vintage Radio Shows :: Archives
Support This Site: Contributors :: Advertise


It is currently Nov Mon 18, 2019 12:39 am


All times are UTC [ DST ]





Post New Topic Post Reply  [ 22 posts ]  Go to page 1, 2  Next
Author Message
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Sat 12, 2003 8:48 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 220
Location: boynton beach,fl. usa
Hi All: I own a Elecronic Measurement Corp. tube tester. I didn't pay much for it and it has always been fine untill now. I am working on a Bush radio from the U.K.. The tube line up is UY41, UL41, UF41, UCH42, UBC41,. U.S.= 31A3, 45A5, 12AC5, 14K7, 14L7,. I can't test these tubes on my machine and I've looked everywhere for an update. What's more, I couldn't find these tubes in my R.C.A. tube manual. I lucked out with the radio, I just replaced the rectifier with a diode and all is well, but now I'm concerned that I will come up against this problem again. Should I think about getting a better tube tester, or has anyone out there ever written their own program for a tube based on data given? Of course in this case I couldn't find any data either. Thanks, Joe <P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Sat 12, 2003 10:06 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 4004
Location: Malone, New York USA
<BR> Ah, Rimlock tubes. I'm not familiar with the EMC tester you have, but I sincerely doubt any update would help due to no 8 pin rimlock sockets being present to begin with.<P> No surprise the RCA manual didn't show these tubes. RCA seems not to list any types they did not produce themselves, let alone those that were european produced, but for only a short time.<P> Even the "better" testers, any I've seen, anyway, that were made for the North American market didn't seem to bother with rimlocks.<BR> If any U.S./ Canadian manufacturer included this capability of testing rimlock (B8A) tubes, I'd sure like to know a make/model #.<BR> I'd buy one in a heartbeat!<BR> <BR> There are sites on the 'net that show data for these types.<P> <A HREF="http://frank.pocnet.net/" TARGET=_blank>http://frank.pocnet.net/</A> <P> Have fun,<P> Den<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Sat 12, 2003 11:05 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 1265
Location: Grand Blanc, MI USA
Out of hundreds of tube testers through the shop--only one (and I still have it) could test rimlock tubes. The winner is the Stark 10-44. This is an enhanced Canadian version of the Hickok 6000 series. Unlike the Hickoks--the sockets are mounted on a larger panel(not on a turret), which includes the rimlock socket, old big pin sockets, octal & miniatures, and Compactron sockets. Data for the 6000/6000A works for this tester. Not a common machine, but a very versatile one.<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Sun 13, 2003 5:41 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 30698
Location: Pocasset, Cape Cod, MA
I don't know why you couldn't make an adapter, provided you could find a socket of course.<P>The AVO VCM163 has a B8A socket and at least some of these were sold in the US (mine was) but as the saying goes on the other side of the pond, they're rather thin on the ground.<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Sun 13, 2003 5:58 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 4004
Location: Malone, New York USA
Thanks for that info, Chris and Alan.<BR> Now I know what testers to "lust" for.<P>-I just won't hold my breath waiting for one...I envision many$$$.<BR> I said I'd buy one in a "heartbeat", but now I won't be so cavalier with my statements!<BR> (Hmm- Let's see what I can sell here for a fund-raiser!) - <IMG SRC="http://antiqueradios.com/forums/wink.gif"><BR> So far, my method is to just buy replacement NOS rimlock tubes- still relatively cheap, the most expensive one costing me $13 U.S. so far- to fill the gaps in my stock.<BR> Probably cheaper than buying one of those "rare birds."<P> Den<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Mon 14, 2003 2:09 pm 
Moderator

Joined: Jan Thu 01, 1970 1:00 am
Posts: 3162
Location: Cockatoo, Victoria, Australia
Hi Joe, You should be able to make an adaptor as Alan suggests provided you can find a socket. I think there have been references to places that sell parts from European sets in the US. You should be able to get a socket from them. I think I can find tubes with similar characteristics in 9 pin versions that will have American equivalents so that you can use their settings. I'll check later.<BR>Don Black.<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 15, 2003 3:40 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 795
Location: Gulf Breeze, FL USA
Please forgive my ignorance, but what is a rimlock tube? I have some 8-pin sockets<BR>that are retained by a circular ring underneath the chassis. Are they rimlock sockets?<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 15, 2003 6:50 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 12549
Location: Mpls, Minnesota
I posted a small picture of a rimlock tube socket in the gallery<P>Dave<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 15, 2003 7:53 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 4004
Location: Malone, New York USA
<BR> <BR> Hi CF,<BR> "Rimlock" style tubes (B8A base) were introduced in europe just following WW2.<BR> A Phillips/Mullard design, IIRC.<P> 8 equally spaced pins with an indexing/locater nub on small metal tube shell at bottom of glass envelope (early) or integral part of glass envelope (later.)<P> Dave's pic in gallery shows the mating recess in the socket shell.<BR> <BR> First number registered in late 1946.<BR> Again, from memory. (A poor one at that.)<P> Became popular in some euro sets around 1948.<BR> They lasted in popularity until around 1953/4, then slowly faded into history, with euro manufacturers adopting the 9 pin "noval" basing.<P> I suppose it was an answer to the all-glass miniature 7 pin types intro'd in N. America just prior to the war. Or 9 pin Novals being developed in N. America during the war, seemingly for military applications at first.<P> Please correct me if I'm wrong on any.<BR> <P> Den<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 15, 2003 1:55 pm 
Member
User avatar

Joined: Jan Thu 01, 1970 1:00 am
Posts: 1797
Location: Armadale, WESTERN AUSTRALIA.
Joe,<BR>The following AVO tube testers had the rimlock socket......<P>Mk2; Mk3; Mk4; CT-160; VCM163.<P>The filament voltage selector on the above testers had all the necessary settings to accomodate the many different heater voltages that the rimlock tubes used.<BR>Ron.<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 15, 2003 4:32 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 795
Location: Gulf Breeze, FL USA
Thanks Guys. You may get me trained yet!<BR>Ben<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Wed 16, 2003 9:49 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 4004
Location: Malone, New York USA
Thanks for the add'l. inf, Ron.<P> Uhh- Would anyone venture an _approximate price on one of those buggers- in today's market?<P> I'd really only want a decent emissions type.<BR> I know diddley-squat about AVO testers.<BR>-- Or Funke, for that matter.<P> (Gotta buy the book- gotta buy the book!)<P> (Preparing my self for "sticker shock.")<P><BR> Den<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Wed 16, 2003 8:47 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 30698
Location: Pocasset, Cape Cod, MA
The AVO MkII, III, IV and the CT160 (military model) are common enough in England, but I wouldn't want to try shipping the first three because of their awkward size. If you have a lot of foreign tubes to test, though, they might be worth considering. For just a few, get a tester with a lot of data available (Hickok, Eico, Heath) and make an adapter, using the test data from the equivalent US tube type. <P>It's worth spending some time with the schematic of an emission tester and figuring out what the selector switches do; then you can set up the tester for anything that comes along. Typically there's a lever for each socket pin, which connects that pin to one of several busses: ground, heater, cathode and plate. Sometimes there's an "open" position, sometimes the ground and cathode are the same, and in dynamic emission models, there's a screen bus. Look at some tubes on the roll chart and see how they're connected.<P>The dynamic emission models (Eico 666) may have a choice of plate and screen voltages. Then there's a switch and/or pot to set the meter current. Pretty straightforward. Just don't get sidetracked by the errors in the Eico charts, wondering why the blazes they did THAT!<BR>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 29, 2003 9:58 am 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 41
Location: Maine, USA
I need an education on tube testers!<P>I don't have one, I just own a bunch of tubes and all the info I can find on tube testers is where to get them and how much they might cost, but not what they do.<P>Well, they test tubes I suppose.<P>But I do that by sticking them in an experimental setup with a bunch of banana plugs, looking up the base info and putting heater voltage as well as plate voltage to the tube and see what happens.<P>Now a tube tester must do that I hope-and better. But what exactly does it test??<P><BR>Hoping for enlightenment<P>Uwe<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 29, 2003 4:39 pm 
Moderator

Joined: Jan Thu 01, 1970 1:00 am
Posts: 37556
Location: Livermore, CA
Hi Uwe<P> You built your own tube tester.. Most tube testers apply voltage and read current. Voltages are not necessarily to the tube manual. <P> Some testers are similar to your bench set up. Eico 666, through levers, allows a person to select voltages applied to each pin. The advantage being you don't have to look for wires to make the setup.<P> Most tube testers also check for leakage between elements.<P>------------------<BR>Norm


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 29, 2003 8:24 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 30698
Location: Pocasset, Cape Cod, MA
The cheaper testers measure cathode emissionm on the theory that most tubes wear out through emission loss.<P>Better testers measure the tube's amplification, by applying some sort of signal to the grid and measuring the amplified signal current on the plate.<P>There are lots of ways to do both tests. Naturally I'd recommend the book "Tube Testers and Classic Electronic Test Gear" for a more detailed explanation. And how to make your own, though you already know that, but I included some material on curve tracing which can be fun to play with.<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Tue 29, 2003 11:35 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 41
Location: Maine, USA
So from what you are saying a tube tester does a fancy version of my basic bench test, I apply voltages and read currents and in one case I also fed a signal in and looked at the amplification.<P>I have limited myself to these parameters because the published info I have seen indicated what those values (and a few others) should be. Maybe I do not look in the right places, but I have never seen resistances between tube elements being published or should one always assume those to be "very very high".<P>Which brings me to the next point, when is a value not good enough? <BR>I see pictures of testers where a meter simply indicates "Good" or "Bad".<P>How is that decided?<P>As always thanks for your help.<P>Uwe<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Wed 30, 2003 8:33 pm 
Member

Joined: Jan Thu 01, 1970 1:00 am
Posts: 30698
Location: Pocasset, Cape Cod, MA
"Good enough" depends where the tube is being used. Emission only needs to be equal to what the circuit draws, but reserve emission is a good indicator of tube life. Gain rarely matters in a properly-designed circuit, but again, low gain usually indicates limited tube life remaining. Gas is always bad as it indicates overload or seal leakage. Interelement leakage causes noise. Grid emission changes the bias which can be a problem in output stages or TV gain-controlled stages.<P>Measuring plate current vs. grid voltage will determine the Gm just as well as applying an AC grid signal, it just takes some calculation or graphical work.<P>------------------<BR>


Top
 Profile  
 
 Post subject: TUBE TESTER UPDATES
PostPosted: Apr Wed 30, 2003 9:15 pm 
Moderator

Joined: Jan Thu 01, 1970 1:00 am
Posts: 3162
Location: Cockatoo, Victoria, Australia
Also, heater to cathode leakage can cause hum. The critical ammount before it causes problems varies with the tube and the circuit it's used in; more of a problem in low level circuits and a grounded cathode is more tolerant than one with a cathode resistor.<BR>Don Black.<P>------------------<BR>


Top
 Profile  
 
Post New Topic Post Reply  [ 22 posts ]  Go to page 1, 2  Next

All times are UTC [ DST ]


Who is online

Users browsing this forum: bob91343, Ed in W. PA, wwcarey and 14 guests



Search for:
Jump to:  




























Privacy Policy :: Powered by phpBB