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Need Lafayette LR-100 information

ADKBob

ADKBob

Well-Known Member
I picked up a Lafayette LR-100 receiver in decent shape and cannot find much information except it is possibly made by Nikko. HiFiEngine has the LR-200 schematic and it looks like the bias adjustment centers the output at half the supply voltage before the coupling capacitor to the speakers. Does anyone have the LR-100 schematic / service / operator manuals or will the LR-200 schematic work for troubleshooting and adjustments? It's stored elsewhere at the moment, so no pics yet. For a smallish receiver, it's pretty hefty. I looked at my 1965 catalog (yard sale find with order form) and it's not in there, so probably made in the late 60s before the LR-200 (circa 1973).
 
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I'd have to go back & look :( I scanned it a long time ago (nowadays I put the year on the photo).
I did see it, I think, in a 1968 catalog recently... I'll do a better scan when I get a chance.
 
Thanks Mark. Take your time. I have so many projects that I'm working on, it's so nice to have the old information. I wish I had kept all of my catalogs instead of starting fires with them.
 
The LR-100 is in the 1971 and 1972 LRE catalogs. It's not in the 1970 catalog, but I -- didn't pull out & look at the1973 catalog :P

I will post a better quality scan anon; gotta do some outdoor chores today.
 
If you can't find the schematic or manual elsewhere, try manualman.com, he seems to sell more Lafayette manuals than anyone else. If you go that route, pm me first.
 
Service info is in Sams MHF-23 from 1972, a quick web search didn't turn up any copies for sale, but they're around. I have most of them, but the paperback binding and tiny print makes scanning a pain.
 
I brought the receiver into the lab to see what she needs. I removed the cover and the insides have some dirt but not as bad as some gear I have opened up before. I plugged in some decent cans since I only used a pair of sacrificial ear buds in the field doing triage. With the internal antenna I tuned to a local classic rock station and I'm listening to AC DC "Back In Black" - how appropriate for the black and silver face. The tuning meter works and gives a maximum reading with just the internal antenna. Mono / Stereo works and the stereo indicator works. No panel or meter lights but that is no big deal. The pots and controls need DeOxIt and Faderlube, but that is why I keep cans at the ready. To get the spraying going I'll have to pull the bottom cover. She seems to be fairly sensitive with stations coming in without an external antenna hooked up. Thanks Mark for the information - I'll call her circa 1972 since the back label is faded. Cool little receiver for $15 - the guy was fairly firm on the $25, but negotiation is part of the fun when hunting / gathering. Oops - Led Zeppelin coming on after the commercials, gotta listen.
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The bottom cover is off. There are some rust in spots and when I get to the cosmetics, would it be alright to use some Naval Jelly to remove the rust, including the screw heads? Also, I'd like to touch up the black paint on the face plate and was thinking of a small brush and a flat black from the hobby shop. Any suggestions?
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DeOxIt is a good buddy of mine. After squirting and exercising all of the potentiometers and switches, the Lr-100 is singing nicely. I hooked up an external wire to the antenna and the FM reception is better. The AUX input works with an IPod, but when you push the button for MONO, it stops the AUX signal - it works fine in FM stereo. I'll try a magnetic cartridge from a bench TT later, but I don't have a ceramic cartridge to test that input.
 
Out of curiosity, I searched that auction site and someone just sold an LR-100 with a date tag of 1968 that had white lettering instead of gold and a black selector switches instead of silver. Maybe these are older than I thought.
 
There are three "fuse" style lamps that were all bad. They are Stanley 8 volt 0.025 ampere. 2 are at the ends of the face plate glass to illuminate the dial and one to light up the signal strength meter. The meter lamp had a green filter sleeve which crumbled at the touch. I replaced all three with 8 volt warm white LED lamps which look nice and should reduce current draw and the temperature inside the case.
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After looking at the LR-200 schematic, it does not appear to be the same circuit as the LR-100. The LR-200 has 4 2SD91 transistors on the heat sink for output, while the LR-100 has 2 2SD91 and 2 GE 12 transistors on the heat sink for output. So, until I come across the schematic / service manual for the LR-100 (free is good), I will just do some more cleaning and button her up. I will hook her up to a pair of Criterion 4X speakers which are a close match for the period.
 
Since it appears no one here had the LR-100 schematic, I talked to a few people and found someone locally who shared my interest in vintage stereo and had the original documentation. I talked the owner of the "rare" schematic into letting me take some pictures of the bias circuitry. It has a 39 volt power supply and a bias circuit adjustment that is temperature compensated with a thermistor attached next to the output transistors. I'll have to get some mini grabber clips on the outputs before the coupling caps to verify half of the supply voltage after measuring the actual supply value. If needed, I'll adjust to half supply voltage. After that, she will be ready to put back together and hook up to some 4X speakers.
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Hello, chiming in on your looking for LR-100 schematic regarding LR-100 lamps for mine that are all out. You answered the fuse lamp replacements which I was looking for, but I can't find what voltage and current rating to replace for the stereo indicator lamp? I like the sound of the unit, and yes the FM picks up well with the internal antenna.
 
ADKBob said:
Since it appears no one here had the LR-100 schematic, I talked to a few people and found someone locally who shared my interest in vintage stereo and had the original documentation. I talked the owner of the "rare" schematic into letting me take some pictures of the bias circuitry. It has a 39 volt power supply and a bias circuit adjustment that is temperature compensated with a thermistor attached next to the output transistors. I'll have to get some mini grabber clips on the outputs before the coupling caps to verify half of the supply voltage after measuring the actual supply value. If needed, I'll adjust to half supply voltage. After that, she will be ready to put back together and hook up to some 4X speakers.
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hi can i have a copy of the schematic of lr 100 please .my e mail is qfm980@gmaI.com regards panos
 
ADKBob was last seen:

Nov 14, 2016

So he probably won't see your request. Maybe someone else can help you.
 
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