I own two CCE SR-5050, a brazilian OEM Kenwood KR-5010 receiver. I swapped the burned STK-0050 for STK-0080 in both receivers with success. The original STKs used to burn due to the grid voltage change, was 110V until the '90s, and now is 127V.
My kenwood kr 6160 has "no low end" on the right channel after it warms up. Im guessing it's an out transistor on the heat sink but my knowledge is limited with electronics. Eventually ill find a tech or figure it out. Thanks for another great video!
Wow this is a good one... I can't wait to see if the discreet board , populated, fits in that spot. It's going to be a cool receiver when you're done, the meters and face are good looking. Thanks for picking the discrete challenge. Cool !!
Had an early 90's sansui with a 100wpc STK chip. Had active cooling on the heatsink so didn't run too hot at full tilt. Had to bypass the protection relays as they were too sensitive. Played fine for years but the power transformer eventually went open during a extended full crank session. Right in the middle of a roudy college party, lots of boo's. Party goers were not pleased!
I have a 4010 that I bought on Craigslist for $20. Had to put a triac across the rotary speaker/power switch. It had nearly eaten itself alive from all the arcing but it works like a charm now. These are somewhat underrated/undervalued in my opinion.
Currently diagnosing a KR-5010 and finding: - Dim bulb tester OK - no shorts. - Speaker relays kick in on start up when connected to mains. - No sound using signal generator through Tape B Play input.
Everyone should own a portable air compressor to blow out your equipment. Also a fuse holder for hard to hold and place fuses. A two inch cheap paint brush helps also. Nice how to video.
I bought some cheap STK modules from Aliexpress and they were legit but used pulls. I did get one bad one in the pulls. it seems somebody is pulling these modules from e-scrap, cleaning them up and selling them. Hey, they did work and I couldn't blow them up
Don’t know if you’ll read this but those Darlington power packs are replaceable they do you can get those replaced or you can actually get a kit that replaces them with two transistors or is it three transitions? I can’t remember but anyway it’s a modified kit that would fit in there. It’s whatever you choose. I see both, but those Darlington power packslook online I found them some on eBay but I’ve also found a lot of over in China which a lot of people don’t like to order stuff from China which I get it but when you can find it it’s not as hard as you think
Could you compare a few kenwood receiver models with pioneer and marantz receivers from that era in terms of sound quality? A friend has a KR-7600, but the sound is somehow more closed to me than the Pioneer and Marantz receivers. With these others, the middle and high tones are heard better than with Kenwood. Maybe he's ready for a refresh, too..
It is best to do your own comparisons. That said, I would rank the popular receiver brands of the time thus, considering only their sound character: Harman/Kardon, Yamaha, Sansui, Marantz, Pioneer, Sony, Kenwood, Sherwood, JVC. Some may want to switch these around, which is OK with me because everyone has their own preferences, and there were other brands that were quite good performers but not as well known.
Xraytonyb has a series on his channel. It's worth watching all 5 parts for details. Fisher RS 2010 Parts 1-5. There are links for the parts lists on Audio Karma but I think some of them are obsolete too. Tony did a great job figuring it out.
Main reason why I am interested in a vintage receiver is the Loudness function. Can’t play music loud enough to enjoy it. Loudness and the right speakers should do the job…
I’ve gone the discrete component PCB many times when replacing these STK packages, enough so that I purchased 100 boards. If you already bought the components that’s great, but I know that some of the components like the TO-220 and outputs are getting harder to get. So if you need any of the components to complete the boards just reach out.
I don't know for certain, but I suspect those ECG/NTE parts are remaining old stock rather than current production, and they are probably Sanyo originals with different labelling.
This Kenwood is unbelievably, incredibly beautiful. I love this gorgeous, classic design.
Good work. Bringing a dead Kenwood to life. I enjoy watching your repair videos. Look forward to more.
Thanks for showing how to clean the tuner pack, because I need to do that on a Harman Kardon 430 Twin I bought. Was afraid to try that method.
Xraytonyb to the rescue. :) I can't wait to see how the two options play out.
I own two CCE SR-5050, a brazilian OEM Kenwood KR-5010 receiver. I swapped the burned STK-0050 for STK-0080 in both receivers with success. The original STKs used to burn due to the grid voltage change, was 110V until the '90s, and now is 127V.
Cool. Xraytonyb has lots of great info in his Fisher RS 2010 series about those modules. Can't wait to see your take on this repair.
Can’t wait to see the next video on this repair…. Thank you….
Looking forward for the next video, great work.
That was my first amp & I wish I never got rid of it, one of the best sounding recievers I've ever owned better than my Marantz from the same Era
My kenwood kr 6160 has "no low end" on the right channel after it warms up. Im guessing it's an out transistor on the heat sink but my knowledge is limited with electronics. Eventually ill find a tech or figure it out. Thanks for another great video!
Wow this is a good one... I can't wait to see if the discreet board , populated, fits in that spot. It's going to be a cool receiver when you're done, the meters and face are good looking. Thanks for picking the discrete challenge. Cool !!
Done right those sanyo STK voltage amplifiers can sound absoulutely beautiful, they died because manufacturers never used adequate cooling.
Had an early 90's sansui with a 100wpc STK chip. Had active cooling on the heatsink so didn't run too hot at full tilt. Had to bypass the protection relays as they were too sensitive. Played fine for years but the power transformer eventually went open during a extended full crank session. Right in the middle of a roudy college party, lots of boo's. Party goers were not pleased!
I have a 4010 that I bought on Craigslist for $20. Had to put a triac across the rotary speaker/power switch. It had nearly eaten itself alive from all the arcing but it works like a charm now. These are somewhat underrated/undervalued in my opinion.
Can't wait for part 2
It-tronics in Germany have most all STK in superb quality ...thanks
Currently diagnosing a KR-5010 and finding:
- Dim bulb tester OK - no shorts.
- Speaker relays kick in on start up when connected to mains.
- No sound using signal generator through Tape B Play input.
Everyone should own a portable air compressor to blow out your equipment. Also a fuse holder for hard to hold and place fuses. A two inch cheap paint brush helps also. Nice how to video.
Nice, look forward to the update videos.
I bought some cheap STK modules from Aliexpress and they were legit but used pulls. I did get one bad one in the pulls. it seems somebody is pulling these modules from e-scrap, cleaning them up and selling them.
Hey, they did work and I couldn't blow them up
Don’t know if you’ll read this but those Darlington power packs are replaceable they do you can get those replaced or you can actually get a kit that replaces them with two transistors or is it three transitions? I can’t remember but anyway it’s a modified kit that would fit in there. It’s whatever you choose. I see both, but those Darlington power packslook online I found them some on eBay but I’ve also found a lot of over in China which a lot of people don’t like to order stuff from China which I get it but when you can find it it’s not as hard as you think
I did one in March. The little brother. The input selector wafer was broken in half and required extensive repair.
Looking forward to more!
STK modules! How can I wait? I must wait. Dang.
Interesting! FM alignment will be a good vid.
Thanks. From where are you buying the PCB replacement for the STK chips ?
Could you compare a few kenwood receiver models with pioneer and marantz receivers from that era in terms of sound quality? A friend has a KR-7600, but the sound is somehow more closed to me than the Pioneer and Marantz receivers. With these others, the middle and high tones are heard better than with Kenwood. Maybe he's ready for a refresh, too..
It is best to do your own comparisons.
That said, I would rank the popular receiver brands of the time thus, considering only their sound character:
Harman/Kardon, Yamaha, Sansui, Marantz, Pioneer, Sony, Kenwood, Sherwood, JVC.
Some may want to switch these around, which is OK with me because everyone has their own preferences,
and there were other brands that were quite good performers but not as well known.
Thanks, do you sell any of these after you repair them?
can you add a link to the discrete design and pcb, pls?
Xraytonyb has a series on his channel. It's worth watching all 5 parts for details. Fisher RS 2010 Parts 1-5. There are links for the parts lists on Audio Karma but I think some of them are obsolete too. Tony did a great job figuring it out.
Yes. I'll put it here as well: audiokarma.org/forums/index.php?threads/stk-0050-replacement-for-sx-780-and-others.721181/
Main reason why I am interested in a vintage receiver is the Loudness function. Can’t play music loud enough to enjoy it. Loudness and the right speakers should do the job…
The trick to ebay powerpack replacements is to NOT bias them. If you try to apply bias as per the service manual, they tend to blow up instantly.
I’ve gone the discrete component PCB many times when replacing these STK packages, enough so that I purchased 100 boards.
If you already bought the components that’s great, but I know that some of the components like the TO-220 and outputs are getting harder to get. So if you need any of the components to complete the boards just reach out.
See ya next time then...👍👍
That is a very poor title of choice which does not do any justice for the content of these videos.
1st 🎉
NTE makes a replacement for the STK that works great no counterfeit
I don't know for certain, but I suspect those ECG/NTE parts are remaining old stock rather than current production,
and they are probably Sanyo originals with different labelling.