Hello everyone. On this past New Year's Day, I pulled the trigger on a really clean, good looking Altec Lansing 710a stereo receiver on Ebay. The unit is most certainly clean, especially being of 1973 vintage. The unit works, it's just that it can't fully amplify 2 book-shelf Klipsch speakers. No matter how I hook it from the back, sound comes out of both speakers, but it's always one that is isn't quite right. So transistor, capacitor etc. problem? Whatever. I tried buying a reproduced service manual of this exact receiver off the website where the guy did everything old school and from home. I'm forgetting his name and business, but I found out earlier last week he had sadly passed away. His website and sheer dedication was very endearing! Just like many others not being able to set an account on "Hifiengine', in this thread, can anyone get me the service manual for this Altec 710a stereo receiver? It would be very appreciated. This is a very nifty discussion forum, many knowledgeable people abound!!
Thank you for the reply! I'd gladly take a PDF of the owner's manual. Thanks again for the response.
The output power of this receiver is limited compared to standards of today.
Do you own a signal generator and scope ? If so we can detect the amp is faulty or not.
Do you own a signal generator and scope ? If so we can detect the amp is faulty or not.
You would think that with 30W/channel, the Altec receiver could adequately a pair of Klipsch speakers. However, it's a 1973 vintage receiver, and that's plenty of time for caps to dry out. and for idle current adjustment pots to open up, especially if they are the cheap open frame carbon type. It would be interesting to see whether the transistors used are Germanium or Silicon.
I own neither. I've tried every configuration with both channels, and with 2 different brand speakers (my old back-up Cerwin Vega book-shelfs). No matter how I wire it, one speaker doesn't want to fully work. ALSO, no matter the channel/speaker, the one that doesn't want to fully work, will kick back some nasty, loud feedback just with the slightest touch of the volume dial, or sometimes just turning the unit on. Once again, thank you folks, for chiming in and giving me resources. It means a lot to me.
Yeah, right? I've only had the cover off of this unit once (a week 1/2 ago). I looked up Germanium transistors on google image search, as well as Silicon transistors, earlier today (thanks to you wondering). I'm pretty sure they are Germanium. It wouldn't be an output transistor, would it? The guts in this machine are incredibly clean looking for a unit that is 51 yrs old. I'm 34 yrs old, and I grew up with records and cassettes, and older audio equipment way before I ever purchased a Compact Disc. I've owned multiple stereo receivers... thing is, this is the first 'Vintage' receiver I've ever purchased. Spent some money on this thing, and there's no way I'm sending it back for a refund. The unit is too clean/looks barely used to get rid of it. Thank you as well for being inquisitive about this problem. I didn't know of this forum until very recently. You are all so helpful (and know a hell of a lot more than I do!).
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It would be worthwhile to 'massage' the front panel switches, especially the Tape/Monitor switch.
Power off the unit and push every switch in and out quite a few times, including rotating the speaker selector and volume and tone controls.
See if that changes anything after power up.
Hugo
Power off the unit and push every switch in and out quite a few times, including rotating the speaker selector and volume and tone controls.
See if that changes anything after power up.
Hugo
Not sure you should work on it without essential tools and instruments. Try to find a teacher in the area.
Have a look at the wiring of the volume control. Efficient products are sold for lubrication of the control
and other pots and switches. It does not matter this item is made using Germanium or silicon devices,
but being 50 years old it surely is silicon.
Yes, I've done that now a few different times. I will say, there was some improvement. The touchiness of the dials/violent feedback settled down a little bit. It's better, but there is still something wrong. I'm not too well-read, especially with older machines.. but what about an output transistor being a problem? Thanks to the member on here from Germany, I downloaded and copied the owner's manual for this unit. Could it be an output transistor/ "heat sink" issue? I never had heard of the term 'heat sink' until the lovely member here sent me the PDF manual. For what it's worth, there are 4 'heat sinks' on the back of this receiver. Thank you for reaching out and providing some tips!! This place is great, and the members are very helpful!
What did you do a few times ? Why do you want to speculate about "output transistor" ?
For a systematic approach you need instruments (which are cheap today) and instructor.
For a systematic approach you need instruments (which are cheap today) and instructor.
I see. 🙂
If there is improvement, clean the contacts with deoxit.
But spray just a tiny bit of it on all mechanical switches and pots. You need to remove the cover, don't spray from the front.
For now, that's all you need to do, don't think of caps or transistors or heatsinks 🙂
Hugo
If there is improvement, clean the contacts with deoxit.
But spray just a tiny bit of it on all mechanical switches and pots. You need to remove the cover, don't spray from the front.
For now, that's all you need to do, don't think of caps or transistors or heatsinks 🙂
Hugo
Kontakt 60 is highly corrosive and not recommended. Kontakt 61 may be used.
In the instructions it is clearly stated that 60 has to be cleaned off after use with a different product.
In the instructions it is clearly stated that 60 has to be cleaned off after use with a different product.
Replying to Netlist's suggestions of rotating the dials back and forth, pushing any buttons that can be pushed from the front panel. It led to some improvement, still something is off. I live in Michigan, EST. I'm about to head out... but I just got done playing 'Miracles' by Jefferson Starship, and things sound better than a couple weeks ago. If I didn't have downstairs neighbors, I would have really cranked it up.
Here are all the specs:
https://www.kontaktchemie.com/KOC/KOCproductsV2.csp
I use Kontakt 60 + Kontakt WL
Of course anyone can do what he/she thinks is best. 😉
Hugo
https://www.kontaktchemie.com/KOC/KOCproductsV2.csp
I use Kontakt 60 + Kontakt WL
Of course anyone can do what he/she thinks is best. 😉
Hugo