I'm just wondering how he determined they were PNP, if he tested or what, you know.
Sansui QRX7001 repair
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It is more likely that the MJ150001 has a different pin-out to the 2SC1111, so Emitter & Base pins are swapped.
I was of the belief that all TO-3 had the same pin-out. From Motorola data sheet...
Sorry, the writing did not show. Anyway, the datasheet shows lower pin in drawing as base, upper pin as emitter, case as collector.
Sorry, the writing did not show. Anyway, the datasheet shows lower pin in drawing as base, upper pin as emitter, case as collector.
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I have always checked against a datasheet as I once had an error on a PCB when I didn't give the PCB layout guy the datasheet with the pinout (wasn't a TO-3 though).
The only datasheet I have found is for the MJ15001, so your metering is correct for that as the +Ve (Red) is on the Base & GND on the Emitter, so the B-E diode conducts. For the MJ part the pin out orientation is set by the package markings.
If you rotate the 2SC1111 through 180degrees and applied the probes, you should see the same response as the MJ15001. I found this bottom view of a 2SC1111 on line. transistor 2SC1111 datasheet
Calibrate to taste.
Owen Smith
1K Club - QQ Shooting Star
Personally I calibrate the rears to have exactly the same volume as the fronts. This is done using test tones generated by the amp or a test DVD/blu ray, and a sound pressure level meter to read the levels and then change the channel gains to make them all the same. Most (all?) content assumes the speaker levels are set like that.
I use Dirac Live and a 13 point mic placement for tightly focused seating area (desk chair). My audio room is a bedroom about 8.5' x 12.5'.
My speaker configuration is 7.1.4.
When I had a true Quad setup 50 years ago or so I tried to place the speakers equidistant from the sweet spot.
Owen Smith
1K Club - QQ Shooting Star
If you are looking for parts for this restoration, QRXRestore sell some:
https://www.qrxrestore.com/parts/
https://www.qrxrestore.com/parts/
Luckily I've now a 6x6m room with the couch in the center = optimal. So 4 equal Speakers at the same volumen.
(4 equal Speakers should always be mandatory because of the frequency respose. Later you can use them also in a 5.1 system)
I'm also using 4 analog VU meters to see what's coming out - the amplifiers are not so well as told by the salesmen, have to correct the potis.
I'm an Electronics Design Engineer and even with all the technical documents mistakes get made! In the case I mentioned, as a Junior Engineer (many many decades ago!) I didn't check the PCB layout sufficiently, and then had to explain to my boss why we had to re-spin the board. I was not popular.
I worked for a company that made boards for the telecom industry. Pretty primitive by today's standards I guess. I identified the problem(s) and handed them off to my co worker who did all the soldering/de soldering.
Saw some strange stuff I never could figure out. Sometimes I'd have my co worker just replace every IC on the board. lol.
We got 99 boards back from one company that puked, and my boss was pissed that I could not repair any over two days and very publicly chewed me out. So he spent a whole day working on them and got one board to work one time. lol.
One signal kept hitting the AND gate before another one (IIRC) and he tried everything in the world to fix it and NADA.
Sorry if I'm going off track here....
Saw some strange stuff I never could figure out. Sometimes I'd have my co worker just replace every IC on the board. lol.
We got 99 boards back from one company that puked, and my boss was pissed that I could not repair any over two days and very publicly chewed me out. So he spent a whole day working on them and got one board to work one time. lol.
One signal kept hitting the AND gate before another one (IIRC) and he tried everything in the world to fix it and NADA.
Sorry if I'm going off track here....
barfle
2K Club - QQ Super Nova
Generally, the recommendation is that all channels are equal - same amps, same speakers, same levels. There are a few purists (not a bad thing) who can achieve that setup, but I have never had that many of the same speakers or amp channels to do that, and I still love listening to surround sound (well, most of the time).
Well my corner speakers are matched. My overhead speakers are matched, though not with the corners. My side surrounds are another type speaker.
My listening position, by necessity, is about, guessing, 4 ft to the rear of the center of the room. My side surrounds are just forward of me.
All speakers point directly at the listening position, save the sub of course.
I have a 29 inch monitor directly in front of me, just below the bottom level of the fronts.
Crazy, but is what it is.
I can't say it would work for everyone, and the calibrations will be retuned when I get my primary AVR back from the shop.
But, I can't emphasize too much how Dirac Live, through the pc app, has helped this crazy room. With a few needed adjustments.
My listening position, by necessity, is about, guessing, 4 ft to the rear of the center of the room. My side surrounds are just forward of me.
All speakers point directly at the listening position, save the sub of course.
I have a 29 inch monitor directly in front of me, just below the bottom level of the fronts.
Crazy, but is what it is.
I can't say it would work for everyone, and the calibrations will be retuned when I get my primary AVR back from the shop.
But, I can't emphasize too much how Dirac Live, through the pc app, has helped this crazy room. With a few needed adjustments.
The MJ15001 should be suitable. You could be right the one that you have might be mislabelled MJ15002's.
There are lots of actual 2SC1111's available for sale on eBay.
The data sheet for the 2SC1111 shows the same pinout as for the MJ15001.
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