Seeking information on Lansing transformers

[kstlfido]

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]

I bet those are peerless transformers.

[kstlfido]

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]

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]

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/image.../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]

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]

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

[NickH]

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

[tomt]

.

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they might be from Reichenbach Engineering Inc.

[Steve Schell]

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...84.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]

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]

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.

Wow, that would be pretty cool. I imagine its a pretty rare until. Of course arent most Lansing manufacturing items pretty rare now a days?

[kstlfido]

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]

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]

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.