Sometimes you have to troubleshoot yourself before you troubleshoot the equipment under repair........
Пікірлер: 48
@ARTHUR-dh5jh2 жыл бұрын
During a repair of my KR 6050 I saw in the service manual that there is no bias current adjustment on the final power amp boards XO7-1700-10. If you look at the board or on the schematic, you will notice they have two resistors positioned in parallel on each board which sets the bias. Example is R1 a 33ohm 1/2 watt resistor and R3 a 22ohm 1/2 watt resistor. In place of R1 I put in a Bourn 0 to 100 ohm 1/2 watt 25 turn trim pot. Did this for R2 on the other channel power amp board as well. Once installed I followed the values as found on page 17 of the service manual and set the current between 20 to 200ma with recommended value of 40 ma. The DC voltage found between the test points 15 and 16 on one board and 17 and 18 on the other should range between 4.4 to 44mv. I can now set the bias and the Bourn enclosed 25 turn pot worked very well. Also, when I bought my used Kenwood and powered it up, sparks came out of my alps switch, which I burnished to get it up and running. Now a few years have passed it looks like I will have to do it again or replace with a toggle or other latching on off switch. Great radio and hope you are enjoying yours. Thanks for the video. Nice job and I always like someone providing helpful info ☝☝
@1959Berre7 жыл бұрын
Thank you for your video's. I really like how you take the time to explain what you are doing. It is kind of relaxing to see how you do things step by step, whithout rushing to conclusions.
@DaveMichalakChannel5 жыл бұрын
As a little comment, the tuning capacitor bearings grease dries out, giving intermittent contact and the scratching noise while tuning. A little shot of Deoxit will clear it up. Thanks for you’re videos. They motivate me to find projects in retirement.
@brig.43987 жыл бұрын
I seem to recall those ads in Stereo magazines for DC receivers. It was a selling point, made us audiophiles think these were the best.
@dednside52294 жыл бұрын
These sounded so good , Kenwood was absolutely underrated It would destroy my new Marantz Easily as this was my first reciever I found it in the garbage. Best amp I ever had , better than my P7000 halfler . Kenwood vintage is the shit
@freddiebell28133 жыл бұрын
I have one of these. Found it at a Goodwill for $30.00 maybe 10-12 years ago. You were right on the money $$$ with the issues associated with the power switch. I saw this in another video, I took mine apart and it was a beeotch to get back together, but I got it back together. As for my tuner section it is incredibly selective. With a basic dipole I'm picking up stations I normally don't even pick up, clearly with my Marantz 2352B or my Pioneer SX950. It's a better than average receiver. Play-test with some JBLs and it is sounds as good as my other higher ones....
@mdzacharias8 жыл бұрын
The lamps flickering with the power switch is a VERY common problem with any Kenwood using that gray Alps box-switch. It will also cause interference on nearby AM receivers. ( The earliest AM transmitters were spark-gaps)
@xraytonyb8 жыл бұрын
I sure found that out the hard way! Hopefully, now that it's cleaned, it should last another 25 years!
@mdzacharias8 жыл бұрын
I've hoarded a couple of those switches. I keep thinking I might pick up a KR-6030 or some such unit at some point. Some versions have an unused set of contacts that can be switched around. Seems like the problem is twofold: insufficient tension on the contacts, and they oxidize over time, making a sort of resistor at the contact points, which burns and makes things worse. I've seen new old stock switches oxidized to the point of having up to eighty ohms contact resistance. I started storing unused switches in a "closed" state - I believe they'll keep better that way.
@glenwhatley41254 жыл бұрын
Solis stage power stages do not require a 'phase inverter'...the genus of the transistors take care of that (;- ). Coupling capacitors along with the accompanying resistors create a phase shift. Also, coupling capacitors are selected to pass the lowest frequency expected so that shouldn't affect ' frequency response'. Personally i agree that back in the 80's the companies were working very hard to convince idiots with money to burn about where they needed to spend their money (;- ). There were a lot of gimmicky things going on.
@RaulHernandez-lg5nw2 жыл бұрын
The IDIOTS we're the sales managers! I worked at Kenwood from 1979 thru 1981! I left the best job I ever had,I was angry the company would not approve the purchase of a 500Mhz counter for the service department! The were spending @ 200K to promote the new car stereo at the time. I was promoted to assistant to the national service manager Mr Mitsuno, @9month after I was hired!We started the SST program (stereo service techniques) which I wrote. They were sent to all our service centers. Kenwood is a great company!! I was honored to meet the founder of Kenwood!!!
@Hortonfarms12 жыл бұрын
I own this receiver and it works great.
@TheC5corvette2 жыл бұрын
I have a MINTY looking model Eleven GX ,,, but dang the thing puts off heat... Even the metal vent screen on the case has come unglued which i think was from the heat.... Looking for any possible adjustments , Bias ??
@davidt84385 ай бұрын
That relay seemed to take twice as long to click on than it should have taken.
@VidelicetMoi5 жыл бұрын
I wish there was greater detail. Details matter.
@jimflys25 жыл бұрын
Really great videos I love them a lot! I have a Kenwood KR 7600 that I have owned since 1987. It's 10 years older than that so it's birthday is around 40 maybe 41 years. It has always had a weak Left Channel. I had a technician measure its output and he said it was about one-third the output of the right Channel. Any ideas at all? I'm going to check the bias voltage tonight, but I am really frustrated and certainly no expert in this area but fairly handy with electronics. The output in the left channel is weaker whether I use the radio or any other input source it is weak in headphones as well as on either speaker a b or c and if I put it to Mono the left side still is weaker than the right. Go figure that.? The volume discrepancy is much more Apparent at very low volumes because of the way sound pressure and loudness works, but I'm really tired of running the balance way over toward the Left Channel. I really really want this correct. Anybody have any thoughts? the pots are all clean and have no crackling in them. I will measure the resistance on the pots tonight as well.
@josephherring233 Жыл бұрын
I have the Kenwood kr 9600 a beast
@josephherring233 Жыл бұрын
2 of them and altec lancing 19
@joanholder-redbear96063 жыл бұрын
So the kr-6050 usually heat up? Because mine does and iam concerned so i guess i need clearnce and why.
@josephherring233 Жыл бұрын
what is the biggest amp you have ever worked on
@showstoppa476 жыл бұрын
Hi! I recently came into this receiver matched with a Technics SL-3350 and two Altec Lansing 893A Corona speakers with what seems like all the original hookups and wiring. I have absolutely no idea how to hook everything up. Would you possibly be able to guide me through it if I sent you images of equipment? Thanks!
@lonnieosbourne818 Жыл бұрын
MY KR 6050 is doing pretty much the same thing..lights flicker power going in and out..
@VNW9168 жыл бұрын
Ei Tony, Since I consider you are an expert, can I ask you for advice? I'm currently repairing a sanyo jcx2300KR and found out one of the STK082 ICs is fried. Do you have any advice where to get a suitable replacement? I know there's quite a few fake STKs out there... Regards, VP
@xraytonyb8 жыл бұрын
You can try your luck at eBay. There are still some new old stock Sanyo STK's out there, but as you said, you have to be careful you don't get a fake or dud. Check the ratings and number of sales for the seller before you buy. That part also crosses over to an NTE1327. Newark electronics has them in stock for around $40. The NTE replacements seem to work perfectly. Just be super careful. The original one blew for a reason. If you had a shorted speaker, you may be OK. But you may also have a shorted power supply, driver transistor or capacitor. Check all the surrounding components before installing the new module or the new one may suffer the same fate!
@VNW9168 жыл бұрын
didn't know about that nte part. I will try to obtain one of those. thanks for the tip!
@andershammer93077 жыл бұрын
Tuner in mine hardly works at all FM is weak and meters hardly move and no MPX stereo. AM is intermittent with a loud cracking noise. So I'm looking for a working replacement tuner board. I know the FM detector coil is shot.
@xraytonyb7 жыл бұрын
The one o this video is in really good shape. I have it boxed up and will be putting it up for sale on eBay soon.
@andershammer93077 жыл бұрын
I don't want to buy another one. I want to fix mine.
@CoolTim448 жыл бұрын
Power output: 60 watts per channel into 8Ω (stereo) Kenwood KR 6050
@eliazarlopez19792 жыл бұрын
Can you please let me Know how to connect all the wires Black together
@fillipedelgado4 жыл бұрын
This schemattics is not the real. Note a Q27 transistor in the IC2 HA12002 protection. Don't have in the document... please, check it!
@josephherring233 Жыл бұрын
we're are you working on these units in Illinois I figure any way I got a Kenwood kr 9600 2 of them and I got , 2 Kenwood basic m2a rated 220 per channel
@ciceroaparecidodossantos-oy5wc Жыл бұрын
Tenho 1 reciver6050 saída queimada
@ciceroaparecidodossantos-oy5wc Жыл бұрын
Será que tem conserto por ser muito antigo
@RogerS08707 жыл бұрын
Hello, enjoyed the video. I also would like to ask your advise. I picked one of these up on eBay. when i hooked it up, nothing. so I started researching and came across your video. I noticed the protection relay did not click in. so i figured it was junk since i know nothing about electronics. Just for the heck of it I unplugged the outputs. turned it on, and the relay kicked in. so my question is, Is it safe to say that the outputs are the problem? I found some on eBay, tested and working. But I do not want to change them if there is a possibility of ruining the new ones. Hope you can help me
@xraytonyb7 жыл бұрын
Thanks for the comment! You really need to test the transistors with a transistor checker or DMM set to diode check mode in order to be sure. Even if you find a shorted output, you may als have a shorted or leaky driver or preamp transistor as well. I would also use a dim bulb tester (see the video on the sx-750 repair for example) when I power it up, so that the current would be limited if there is a short.
@RogerS08707 жыл бұрын
thanks for the reply, I know nothing about electronics LOL. I have a DMM , but I am not even sure how to use it. I wouldn't even know what to test if I did know how to use it. I wish we had a repair shop I my area, so I don't ruin this unit. I really like it. Thanks again.
@RogerS08707 жыл бұрын
Hi Tony! Well after trying the new outputs, no luck. Still no sound, or meter movement. I did take it to a local repair shop, and after some transistor and cap replacement, nothing. I would like to ask if you would be willing to look at it if I shipped it to you? I I would certainly pay you for your time. If you are interested I can give you my contact information. Thanks!
@xraytonyb7 жыл бұрын
That's the problem with these direct coupled systems. Really hard to troubleshoot. Also, if one component fails, often other parts will fail as well. I would be willing to look at it, but I have a couple of other things in line for the bench first. If you want, you can give me your e-mail and I'll follow up with a few other questions so I can get an idea of what's going on first.
@RogerS08707 жыл бұрын
ok, the shop that has it now said he wanted to do some more research, but I think I'm going to just pick it up and bring it back home. If you need to contact me my email is roger0870@sbcglobal.net Just let me know what you need and when. Thanks again!
@andershammer93076 жыл бұрын
Still looking for a tuner board or detector transformers for mine. I get some FM but no stereo.
@andershammer9307 Жыл бұрын
It's fixed now. I got a detector transformer.
@timothyweahry34647 жыл бұрын
I noticed your schematic was for a KR6650.
@xraytonyb7 жыл бұрын
They are pretty much the same. I think one is just a newer model year than the other.
@CoolTim448 жыл бұрын
I would recap it
@jimr31794 жыл бұрын
WOW,It's amazing how all the other companies(Marantz,Sansui,Kenwood,and Technics copied Pioneer.There are those that will argue on who was first with that look.BUT IT WAS PIONEER!