Seeking information on Lansing transformers [Archive]

kstlfido

12-18-2012, 11:17 PM

Hello folks- New member here, though I've been visiting this site for years.

I am trying to identify some Lansing transformers on an amplifier I found. Pic attached. It's a bit rusty. Chassis and transformers are in a dark blue. I can barely make out the part numbers on the transformers- TU-504 and TJ-151. I believe they are choke and output, respectively.

The site's library doesn't have info on these, though there are some similar part numbers in the Altec Lansing transformer catalog. The amplifier appears to be a rack-mount affair with two 6SJ7's and two 6L6's.

Any help would be greatly appreciated.

Thank you- Kent

NickH

12-19-2012, 06:26 PM

I bet those are peerless transformers.

kstlfido

12-27-2012, 12:53 AM

Thanks NickH. Yup, I figured they might be. But I can't find any data on them. I'm hoping someone here might help me out.

NickH

12-27-2012, 07:08 AM

Thanks NickH. Yup, I figured they might be. But I can't find any data on them. I'm hoping someone here might help me out.

Send an email to Mike Lafevre at Magnequest. He owns all the old peerless documentation. If anyone could let you know it would be him. You can reach him on audio asylum. I believe theres a Magnequest forum there wich he runs.

Nick

Steve Schell

12-30-2012, 03:07 PM

Kent, I cannot find those part numbers in any of my literature. Those "A Lansing Product" decals are typical of Altec Lansing production from roughly 1942 to 1945, then the red, white and blue decals took over. I note with interest that the chassis is also painted the typical Lansing blue; perhaps the amp was an Altec Lansing product. Amplifier production had begun by 1939 with a push pull 6L6 amp for the Iconic, described here:

http://www.lansingheritage.org/images/lmco/advertizements/1939cat-1.jpg

The subject of amplifier building was discussed in a 1937 letter written on the Lansing Mfg. Co. letterhead by Dr. John Blackburn. You may find it interesting, as it details your amp's origins. Your transformer and choke were likely designed by either Ercell Harrison or Colin Campbell. Harrison had pioneered the design of wide bandwidth audio transformers at LMCo. beginning in the early 1930s, later heading up Peerless after Altec acquired them at some point in the 1940s. Campbell was a magnetics engineer who was Altec's plant manager through the mid 1940s.

Kent your amp, if actually an Altec product, is a rare bird from a time that Altec was just beginning to ramp up into being a major electronics producer. Could you post a few more pictures of it, including some shots of the underside?

NickH

12-31-2012, 06:58 AM

Its funny how they are reffereing to the 2a3 as a high output tube. But I guess it was in those days.

I guess nothing has changed. Everyone loves the 45 then and now.

Steve Schell

01-01-2013, 01:59 AM

NickH I prefer the 45 to the 2A3, for basically the same reasons as detailed by Mr. B. Eternal truths I suppose...

NickH

01-02-2013, 03:02 PM

Ive only heard 1 single ended 45 amp. It was made by Kevin Kennedy and it sounded stellar.

tomt

03-12-2013, 10:11 PM

.

.

they might be from Reichenbach Engineering Inc.

Steve Schell

03-19-2013, 11:39 PM

New sh** has come to light, man, as "the Dude" would say. A friend of mine managed to win an ebay auction for a **beyond rare** Lansing Iconic tube power amplifier and accompanying beefed up dual 5Z3 rectifier field supply that both powered the field coils and provided B+ to the amp. The completed auction is, for the moment, located here:

http://www.ebay.com/itm/190798175351?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

These pieces were delivered to me and I took them to a mutual friend, an expert tube amp builder and repair technician. He replaced the electrolytic caps in both pieces and the coupling caps in the amp, installed good tubes and began bringing them to life on a variac. Once up to full voltage he made performance measurements of the amp and it is a honey! Ercell Harrison's output transformer offers astounding performance for a 1940s amp. With the feedback loop in place the response from 20 Hz. to 20 kHz. is ruler flat, and with the loop opened up it is still only down 2.4 dB at 20 Hz. and .9 dB at 20 kHz. Distortion at one watt is only .25% with feedback and only .9% without. Not many current transformers would do this well! This basic amp circuit was incorporated with input switching and preamp circuit as the Altec Lansing A323A, which has been bringing significant money in recent years. Ercell Harrison is considered in some circles as the father of modern wide bandwidth, low distortion audio transformer design, responsible for most of the great Peerless Iron of the 1950s. This rusty little Lansing Iconic amp, along with Dr. Blackburn's letter that I posted previously, verifies that his track record of excellence began at least as early as the late 1930s.

That ebay auction will disappear soon, so here are the auction pictures of the amplifier and field supply:

Steve Schell

03-19-2013, 11:54 PM

Kent I just reread your thread-starter post and noticed that your tube complement is the same as that of the the Iconic amp. Your transformers may be the same as the Iconic amp, only potted in for use in your industrial or theatre rack mount amp. If your transformer is the same as the unit I have discussed then you have something really special. If you are still following this thread then speak up... more pics of your amp would sure be appreciated.

NickH

03-20-2013, 10:40 AM

kstlfido

03-20-2013, 11:52 AM

Hi Steve-

Thank you for the information. Interesting! Attached are some more pics taken that day. The speckles on the chassis are water drops as it was trying to rain when I was taking pics. I hope these help. I'll need to do a light clean and take some more, if you wish.

The only decal on the chassis is from a storage company. This was on a few of the items in the garage where this was found, in southern CA.

I'll check the DCR's of the transformers in a few days.

Cheers- Kent

NickH

03-20-2013, 02:29 PM

Thats going to be a tough one to clean. Your probably going to have to strip the chassis of all the components. Then get someone to media blast it. At least thats what I would do. Just out of curiosity why are you looking for info on the transformers?

Justby seeing the under chassis photo I can tell a few things. The large potted trans looks like the output. The little one in the middle is the choke and the none potted one is the power. You should be able to tell if they are ok by just using an ohm meter. I WOULD NOT put power to it though. Not without a complete rebuild of it. I would test the transformer with the leads dis connected. That why theres nothing that can get damaged. That is unless you have a shorted winding. In that case its already toast. Just dont want it to toast something else.

You realize you might have to do this the hard way and generate a schematic. Then with thepower trans removed look at the secondary voltages.

Nick

Hi Steve-

Thank you for the information. Interesting! Attached are some more pics taken that day. The speckles on the chassis are water drops as it was trying to rain when I was taking pics. I hope these help. I'll need to do a light clean and take some more, if you wish.

The only decal on the chassis is from a storage company. This was on a few of the items in the garage where this was found, in southern CA.

I'll check the DCR's of the transformers in a few days.

Cheers- Kent

kstlfido

03-20-2013, 03:06 PM

If I had transformer info, I could possibly better identify/figure out schematic. Yes, I know the large potted transformer is the output, smaller is choke. IIRC, the output # is similar to some in the Altec transformer list; the "J" possibly indicating line output (5-600 ohm). A DCR check will determine that quickly.

Tracing out the circuit shouldn't be too difficult.

I'm hesitant to strip/blast and clean in that fashion just yet. It may be a bit ugly (!!), but it is original. Let's see if it can be identified first. I'll give it a good cleaning with mild cleaner, though.

NickH

03-20-2013, 08:08 PM

Those filter cap will become dead shorts if a.c. is applied to it. They may just explode or they could damage the power trans. Be careful.

And good luck getting it running.

If I had transformer info, I could possibly better identify/figure out schematic. Yes, I know the large potted transformer is the output, smaller is choke. IIRC, the output # is similar to some in the Altec transformer list; the "J" possibly indicating line output (5-600 ohm). A DCR check will determine that quickly.

Tracing out the circuit shouldn't be too difficult.

I'm hesitant to strip/blast and clean in that fashion just yet. It may be a bit ugly (!!), but it is original. Let's see if it can be identified first. I'll give it a good cleaning with mild cleaner, though.

kstlfido

03-20-2013, 08:25 PM

In it's present condition, I'm not even thinking of plugging it in - even on a metered Variac! I'm very familiar with old components. Used my TO-4 to reform a few 'lytics. But these are probably beyond reforming judging by the general level of corrosion. Frankly, all the components are suspect, though I've had better luck with old resistors.

I'm not going to touch the components until I figure out what it is. Thank you for the heads-up though!

NickH

03-21-2013, 06:36 PM

To-4, I'm not familiar with that except the semiconductor package. I'd bet you a couple buck that the iron is still good. The only thing that would kill them beside catastrophic failure is being submerged in water. It doesn't look like either of those problems have happened. No black tar leaked out on the underside of the chassis.

Anyway, sounds like you've got a plan. You have a pretty cool little project there. Keep us posted.

Nick

In it's present condition, I'm not even thinking of plugging it in - even on a metered Variac! I'm very familiar with old components. Used my TO-4 to reform a few 'lytics. But these are probably beyond reforming judging by the general level of corrosion. Frankly, all the components are suspect, though I've had better luck with old resistors.

I'm not going to touch the components until I figure out what it is. Thank you for the heads-up though!

mech986

03-22-2013, 02:11 AM

To-4, I'm not familiar with that except the semiconductor package. I'd bet you a couple buck that the iron is still good. The only thing that would kill them beside catastrophic failure is being submerged in water. It doesn't look like either of those problems have happened. No black tar leaked out on the underside of the chassis.

Anyway, sounds like you've got a plan. You have a pretty cool little project there. Keep us posted.

Nick

He's referring to the Sprague TO-4 Capacitor checker:

http://www.ohio.edu/people/postr/bapix/capchkrs.htm

58471

I'm guessing this amp probably was stored near the waterfront, judging by the corrosion all over. Will be quite the project. Extensive pictures will be needed to document where everything goes on the wiring harnesses.

Steve Schell

03-23-2013, 05:27 PM

Kstlfido, thanks very much for the additional pictures. It appears that your amp is virtually the same circuit as the Iconic amp, but installed in a rack mount chassis. Your silver power transformer doesn't match the others, but the installation looks original as best I can tell. One oddity with the Iconic amp and field supply iron is that all the end bells are stamped "Inca Transformer Co., Los Angeles" with the logo with the design of an Inca fellow in profile. Perhaps by this time Inca was building some transformers for Altec to their specs... hard to say.

At some point in the mid or late 1940s Altec Lansing purchased the Peerless Transformer Company, and Ercell Harrison became their chief engineer or at least contributed many significant designs to the new Altec division. He is credited with designing the Peerless 20/20 and 20/20 Plus audio transformers.

I recently visited my friend who got the Iconic amp and field supply running, and it sounds great.

NickH, you are correct that all Lansing Manufacturing Company products are now very rare, even here in the Los Angeles area. The Iconic amp and field supply are in another category, I suppose "beyond rare" as I have seen or known of perhaps thirty Iconics in the past dozen years, but only two of these amps and field supplies.

NickH

03-23-2013, 08:18 PM

Make it so much more cool when you get it running again. It looks ruff but I bet it can be fixed.

Ah, a cap tester. I should have though of that. How much voltage does it apply when it tests the caps?

Steve Schell

03-23-2013, 10:42 PM

A capacitor checker is above my pay grade, but I think it's safe to say that any 70 year old electrolytic filter cap should be replaced with new in every case. These things have a designed service life of 15 or 20 years and anything beyond that is iffy. In this case iffy would refer to the future life of precious tubes, vintage transformers and chokes that should be protected at all reasonable cost.

Some friends and I built a dozen reproduction Iconic 330 VDC field supplies a few years ago and we bought the electrolytic caps from Antique Electronic Supply in Tempe, who apparently bought the old Sprague equipment and put a good portion of their old product line back into production. These caps have been perfectly stable and reliable in operation, and should be considered for installation before powering up any valued old gear that uses electrolytics.

Kstlfido you seem knowledgeable technically, and can no doubt upgrade your amp and get it up and running well yourself. If however you would like to be put in contact with my friend the restoration guru supreme, just let me know. I think you have a very significant amp, one of the very first Altec industrial power amps. I wouldn't worry too much about the rust; the Iconic amp and field supply is fairly rusted up but delivering beautiful sounds at present.

Altec Best

03-25-2013, 10:12 AM

Nice find there Kent ! :bouncy:

kstlfido

03-26-2013, 01:46 AM

Finally got the amp on the bench. Did a a small bit of cleaning- it came up a little bit but the rust is pretty extensive. Thanks, Steve for the Inca tip. I did get a *little* info on this power. All I could find was "1121" stamped on the top label.

Starting to map out the circuit. Took some transformer DCR readings. They seem to be OK.

Power-
Primary- 2ohms (110v tap- not used); 2 ohms (120v tap- used).
Secondary-
B+: 45---0---45 ohms.
5V for 5Z3: 0.4 ohms
6.3VCT for 6SJ7, 6L6: 0.4---0---0.4 ohms.

TU-504 Choke- 87 ohms.

TJ-151 Output transformer-
Primary- 4 taps. 151---0---0---150 ohms. 0 taps connected.
Secondary- 6 taps. 21.7---21.2---0---0---22---22.5 ohms. 0 taps connected. First and last taps unused.

Looks like the OPT is indeed line output, not voicecoil.

More info as I gather it!

Cheers- Kent

NickH

03-26-2013, 05:09 PM

600 ohms, odd. What are the tubes, 6l6? One hell of a line out. You could probably get a matching transformer to get a more usable range.

Nick

Finally got the amp on the bench. Did a a small bit of cleaning- it came up a little bit but the rust is pretty extensive. Thanks, Steve for the Inca tip. I did get a *little* info on this power. All I could find was "1121" stamped on the top label.

Starting to map out the circuit. Took some transformer DCR readings. They seem to be OK.

Power-
Primary- 2ohms (110v tap- not used); 2 ohms (120v tap- used).
Secondary-
B+: 45---0---45 ohms.
5V for 5Z3: 0.4 ohms
6.3VCT for 6SJ7, 6L6: 0.4---0---0.4 ohms.

TU-504 Choke- 87 ohms.

TJ-151 Output transformer-
Primary- 4 taps. 151---0---0---150 ohms. 0 taps connected.
Secondary- 6 taps. 21.7---21.2---0---0---22---22.5 ohms. 0 taps connected. First and last taps unused.

Looks like the OPT is indeed line output, not voicecoil.

More info as I gather it!

Cheers- Kent

Steve Schell

03-26-2013, 08:07 PM

Thanks for the transformer specs, Kent. I'm thinking your amp either drove a distributed line, like a bunch of transformer connected ceiling speakers, or perhaps drove the grids of a high power booster amp.

I have a book published by RCA Service Company in 1950 that has several pages listing the Altec transformers and chokes, updated as recently as 1946. The numbers on Kent's components do not appear, though there is an output transformer called a TJ-152A which may be a close cousin to the TJ-151. Here is a scan of that page:

kstlfido

04-28-2013, 08:02 PM

Thanks, Steve. It does seem similar. Maybe the TJ-151 is similar to the 152, but without tertiary windings? Also, the secondary DCR's don't seem to be high enough for such high output impedance. But yes, seems to be a similar animal!

I cleaned it up. Just a mild detergent and a toothbrush. Careful brushing and compressed air. Then finished the outside with a light rub of beeswax. Looks a lot more presentable now!

-Kent

NickH

04-29-2013, 03:50 PM

Wow, she cleaned up pretty good.

kstlfido

04-29-2013, 10:53 PM

...and smells good! Howard's Feed N' Wax. :D

NickH

04-30-2013, 08:54 AM

...and smells good! Howard's Feed N' Wax. :D

Ill have to check that stuff out.

Nick

kstlfido

05-12-2013, 04:44 PM

Due to some recent family matters, I've decided to part ways with the amplifier. I just don't see the time in the forthcoming years to deal with restoring it.

http://www.ebay.com/itm/140975233168?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

Thank you all for the help!

Best- Kent

NickH

05-13-2013, 06:09 PM