Issue(s) with Kenwood KD770D

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JackD

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Re: Issue(s) with Kenwood KD770D
« Reply #20 on: 8 Feb 2013, 08:55 pm »
If the seller lowered the arm all the way down  for shipping and did not lower the arm elevator assembly too then the elevator assembly needs to be lower until you zero balance the arm set the VTF and set it on the record to check the VTA.  Then once you raise the arm to the right place you can reset the height of the elevator assembly to lift the stylus tip 5-7mm off of the record.  So for now loosen the screw Neobop alluded to and lower the elevator assembly all the way down and then start the process.  Once it is all the way down then you can see if pushing the button does anything.   Or he may have run the arm elevator all the way up for shipping instead.

neobop

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Re: Issue(s) with Kenwood KD770D
« Reply #21 on: 8 Feb 2013, 09:23 pm »
Also, looking at your picture, Neobop, looks like the elevator mechanism on yours is lifted off the plinth. Well, mine is all the way down. I gently pulled on the entire assembly by holding on to the base of the elevator assembly, and the whole assembly slides easily upwards and when I release it, slides back down. Neobop - Are you able to do the same thing with your elevator assembly?

Not sure what this means now. So even with the elevator mechanism all the way down, the stylus does not make contact with the LP. Obviously there's some height adjustments to make.

But I really want to figure out the elevator mechanism too. According to the manual, the TT should power up in the UP position. Nothing of the sort is happening.

The cueing mechanism is only one part of the arm assembly, that includes the bearing housing, anti-skate mechanism etc.  My entire assembly is lifted off the plinth because that's the height where I have my arm set. This is adjusted by loosening the 2 allen bolts and then tightening at desired height.  If your whole arm just slides up and down, you need to tighten those allen bolts at an appropriate height. 

When the record ends, the sensor triggers the cueing servo and the arm lifts off the record. I stop the platter and push the arm back to the rest.  The cueing stays up until I hit the button again, even if I turn off the table. When I turn it on later, the cueing is still up, until I hit the button.  The pic is with the the cueing up, because I didn't turn on the power and hit the cue button. So what you're seeing is both the arm raised to the height I want, and the cueing up.  Both of these functions can be adjusted independently of the other. I can change the cueing height without changing the arm height.

I'll take some more pics if it will help.
neo

Maritan

Re: Issue(s) with Kenwood KD770D
« Reply #22 on: 8 Feb 2013, 10:05 pm »
Roscoe/ Neo - I will take pictures later tonight and post them.

I checked the assembly for lift during a quick visit home at (late) lunch time. Once I get home for the evening, I'm cancelling plans for Friday night and going to check the damn TT out.  :thumb: I'll start taking things apart and can post pictures as I go if anybody things it will help or if you just want to see them.

Neo - Any tips/ suggestions you have that you think could help a first time vinyl/ TT owner specifically with the 770D, please do share with me. Over PM, in this thread here, or hell, I'll PM you my phone number and we can talk at a time of your convenience.

Thanks for everyone's input so far.  :)

neobop

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Re: Issue(s) with Kenwood KD770D
« Reply #23 on: 8 Feb 2013, 10:27 pm »
Roscoe/ Neo - I will take pictures later tonight and post them.

I checked the assembly for lift during a quick visit home at (late) lunch time. Once I get home for the evening, I'm cancelling plans for Friday night and going to check the damn TT out.  :thumb: I'll start taking things apart and can post pictures as I go if anybody things it will help or if you just want to see them.

Neo - Any tips/ suggestions you have that you think could help a first time vinyl/ TT owner specifically with the 770D, please do share with me. Over PM, in this thread here, or hell, I'll PM you my phone number and we can talk at a time of your convenience.

Thanks for everyone's input so far.  :)

Words of caution - I have no idea what your situation is, or what your plans were, but the WAF (wife acceptance factor) could be dramatically impacted when you start cancelling Friday night.  If you're married, She who must be obeyed, should be considered.  If she starts hating your damn table, your hobby would be affected, and not for the better.

We're here to help.  Whatever's needed.
neo 

Nick77

Re: Issue(s) with Kenwood KD770D
« Reply #24 on: 8 Feb 2013, 10:32 pm »
If the seller lowered the arm all the way down  for shipping and did not lower the arm elevator assembly too then the elevator assembly needs to be lower until you zero balance the arm set the VTF and set it on the record to check the VTA.  Then once you raise the arm to the right place you can reset the height of the elevator assembly to lift the stylus tip 5-7mm off of the record.  So for now loosen the screw Neobop alluded to and lower the elevator assembly all the way down and then start the process.  Once it is all the way down then you can see if pushing the button does anything.   Or he may have run the arm elevator all the way up for shipping instead.

I had this same problem when i received a vintage Sony TT after shipping, I had to psychically push down the elevator assembly so the arm would engage the album.

Maritan

Re: Issue(s) with Kenwood KD770D
« Reply #25 on: 11 Feb 2013, 01:53 am »
So, after a little digging here's what I found:

The solenoid is NOT seeing a signal. I'm not sure if the solenoid itself works, but I'm not sure how to test that.



I see a signal all the way into the base of transistor Q9, but no output. I connected a scope to "5" as shown in the circuit above and I didn't see any signal. I didn't see anything on "6" either. The diode D6 checks out fine. I'm not sure about the capacitor. I need to check that out. I can't say for sure that Q9 is shot. I'm not sure how to check that out either.

When I physically push on the solenoid "shaft", it lowers the piece that sits under the elevator assembly. When I do this, the crescent shaped assembly (elevator platform?) lowers and allows the tonearm to lower to the platter. The elevator platform is already adjusted to its minimum height.

I'm going to play with the adjustments - both tonearm assembly height and the elevator platform height to see if I can just play a record.

Any suggestions are welcome.

neobop

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Re: Issue(s) with Kenwood KD770D
« Reply #26 on: 11 Feb 2013, 04:39 pm »
Maritan,
Maybe someone at the circle called "The Lab" or DIY Audio could help you figure it out.  If you applied 12 or 20V to the solenoid, wouldn't that test it?  I'd be inclined to just replace cap C19 and resistor R17.  They say that it's usually old caps and resistors that fail, but I'm no tech.  Speaking of which, I'll see if I can get a hold of my tech.  He fixes tons of old equipment and might be able to tell me about the transistors.

I think you might have to remove the shaft holding up the elevator platform, to play a record in fully manual mode.  It's a shame this "working perfectly" table isn't so perfect. 
neo

Maritan

Re: Issue(s) with Kenwood KD770D
« Reply #27 on: 11 Feb 2013, 04:59 pm »
I didn't have a DC voltage supply at home. I'll have to bring the TT into work and see if I can check things out with that. I really suspect the cap C19 is bad, but unless I cut it out of the PCB, I can't truly check it - all the additional/ stray capacitance on the line will cause a false reading if C19 is measured in-circuit.

I also have a confession to make: John Coltrane was in the house yesterday!  :thumb: (I will start another thread with my thoughts about this experience.)



It plays in "manual" mode and it plays beautifully. I basically "tied" down the elevator platform and that was all she needed. All that said: The TT is NOT as advertised by the original seller. It works, obviously, but not in "perfect" working condition.

My question to my fellow vinyl enthusiasts is as follows: Should I look into returning the 770D and buy something locally so I can see and hear it work before I buy it? Here's a sample of what I saw locally (and all listed as working flawlessly):

1. JVC QL F6 -$100
2. Micro Seiki DD-31 - $275 obo
3. Dual 731Q - $175
4. Yamaha YP-D6 - $175 obo
5. Pioneer PL400 - $95 obo
6. Sanyo TP 1012 - $65

Are any of these tables inherently better or as good as the 770D?

If that's the case, my options open up. I could return the 770D and pick one of these up locally. Any input will be appreciated.

Thanks!

pumpkinman

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Re: Issue(s) with Kenwood KD770D
« Reply #28 on: 11 Feb 2013, 06:04 pm »
FWIW I'd return the Kenwood and look into the Micro Seiki. 

usp1

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Re: Issue(s) with Kenwood KD770D
« Reply #29 on: 11 Feb 2013, 06:30 pm »
Maritan - Where is local? That is avery nice collection of local options.

Maritan

Re: Issue(s) with Kenwood KD770D
« Reply #30 on: 12 Feb 2013, 03:42 pm »
Ok, one vote for the DD-31.  :lol: Pumpkinman - Do you have any info on that model? I couldn't find ANYTHING except one video of the same model. I found negative info on the DD-30 and DD-33, and that makes me a little wary of the in between model DD-31.

usp1 - My location is Arizona. I agree with you, it seems like a decent selection.

Neobop - Any input from your tech?

Anybody else have any input on what your choice would be? Fix the 770D or return it? If you think I should return it, which of the above mentioned TTs would you recommend as a good substitute that is not a terrible step down from the Kenwood?

JackD

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Re: Issue(s) with Kenwood KD770D
« Reply #31 on: 12 Feb 2013, 04:10 pm »
My vote is for the JVC, I own one

http://www.thevintageknob.org/jvc-QL-F6.html

neobop

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Re: Issue(s) with Kenwood KD770D
« Reply #32 on: 12 Feb 2013, 05:41 pm »
I didn't have a DC voltage supply at home. I'll have to bring the TT into work and see if I can check things out with that. I really suspect the cap C19 is bad, but unless I cut it out of the PCB, I can't truly check it - all the additional/ stray capacitance on the line will cause a false reading if C19 is measured in-circuit.

It plays in "manual" mode and it plays beautifully. I basically "tied" down the elevator platform and that was all she needed. All that said: The TT is NOT as advertised by the original seller. It works, obviously, but not in "perfect" working condition.

My question to my fellow vinyl enthusiasts is as follows: Should I look into returning the 770D and buy something locally so I can see and hear it work before I buy it? Here's a sample of what I saw locally (and all listed as working flawlessly):

1. JVC QL F6 -$100
2. Micro Seiki DD-31 - $275 obo
3. Dual 731Q - $175
4. Yamaha YP-D6 - $175 obo
5. Pioneer PL400 - $95 obo
6. Sanyo TP 1012 - $65

Are any of these tables inherently better or as good as the 770D?

If that's the case, my options open up. I could return the 770D and pick one of these up locally. Any input will be appreciated.

Thanks!

I had to look up some of those tables.  The Micro Seiki looks nice, but not a contender IMO and I think it's even older than the 770, if that makes any difference.  It doesn't have a coreless/slotless motor like the Kenwood, but it has a nice MA-707 arm - also straight.  It's DC servo controlled rather than quartz locked.  When speed gets erratic on a servo, you can often fix it by spraying the pot, not always though. The Yamaha looks like a decent table.  I don't know much about it, although I really think you'd have to go higher up the food chain, on either line, to equal the 770.

I spoke to my tech and he said that those ceramic caps almost never go bad.  He was almost positive that the transistor is available, but without seeing the schematic, didn't know how the circuit is configured.  When he starting telling me about 3 different ways you could hook up a transistor, and the different ways to configure a circuit like that, I got lost.  He also said that you should check out the solenoid.  It could be physically blocked or impeded.  It could have been in the garage for a few years and the silicone damping fluid could be hard, or have some dirt in there.  The solenoid itself should have around 800 ohms resistance, but that figure could vary quite a bit, > 100, < 1K.  He also said to make sure the board isn't cracked or have a bad wire or connection.

When I got my 770, a few years ago, I was thinking of taking it off the plinth and making a custom table out of it, with another arm.  The dust cover was broken in transit and the plinth was scratched.  After I heard how it performed, I decided to keep it as-is.  I bought a replacement dust cover ($140) and cleaned up the plinth.  Even though the cueing doesn't work, you should consider keeping it, or possibly selling it to one of us, if someone is interested. You got a great deal on that table and I don't think it would take that much to fix.  When I saw that ad for the table I wanted to buy another one for myself. But I need to downsize and I'm going to sell a couple of tables.  Not the 770 though.
neo   

usp1

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Re: Issue(s) with Kenwood KD770D
« Reply #33 on: 12 Feb 2013, 06:10 pm »
Maritan - whatever is ailing your TT it appears to be contagious!  :duh:  Now my TT seems to be having trouble as well. The autocue drop has become intermitent on my TT as well. I can push down on the lifter and make it work and it does autolift at the end of the record. Anyway, I may have to start a new thread so that I do not hijack yours.

JackD

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Re: Issue(s) with Kenwood KD770D
« Reply #34 on: 12 Feb 2013, 06:52 pm »
USP1

You need to get Deoit into that switch and work it.  Also sometimes those switches are finicky about how they are pushed.

Maritan

Re: Issue(s) with Kenwood KD770D
« Reply #35 on: 13 Feb 2013, 05:40 pm »
USP1 - Sorry to hear that, but it is a little funny.  :lol:

Neobop - Thank you very, very much. That is GREAT information and gives me what I need to go ahead and hopefully finish up my troubleshooting. I'm going to figure out how to disconnect the solenoid from the two posts (I think they're wire wrapped instead of soldered) and test both the solenoid and the transistor. I found an equivalent transistor for the 2SD882 that drives the solenoid, but I haven't looked to see if I can find a replacement solenoid if that's what I end up needing.

Where did you get your dust cover? The one I have was cracked in transit.

(Extremely poor quality) Pics of my troubleshooting to follow.

neobop

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Re: Issue(s) with Kenwood KD770D
« Reply #36 on: 13 Feb 2013, 07:47 pm »
Here's the phone number.  This guy is in Florida and has all the dimensions etc.  Just tell him what you have.  The 770 cover is more expensive than some, because of size and thickness.  Nice replacement cover though. 
 http://www.turntabledepot.com/home.php

I read some comments about the JVC QL F6, that weren't particularly flattering.  Now that I see the info in Vintage Knob, it seems like a great buy for $100.
neo




JackD

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Re: Issue(s) with Kenwood KD770D
« Reply #37 on: 13 Feb 2013, 08:05 pm »
Neo

If I way in his area, I would have bought it already.  They rarely show up on Ebay and when they do go for many times that price.  Plus it being mechanical it eleminates some of the problems the electronic control versions have.  Another nice thing is being able to adjust the damping in each plane seperately. 

Maritan

Re: Issue(s) with Kenwood KD770D
« Reply #38 on: 13 Feb 2013, 08:14 pm »
Interesting.

I wonder which one would be better in a "shoot-out". They are very identical in specifications, so I really am curious to know. Any insight from you JackD?

Will the JVC accept the AT100E cartridge? If so, maybe a head to head comparison can be arranged...  :wink:

What kind of cartridge does the JVC do well with? Low compliance? High compliance? MM/ MC? Any suggestions of carts for the JVC? That will give me something to look up.

Thanks for the link, Neo. Appreciate all the help so far.

JackD

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Re: Issue(s) with Kenwood KD770D
« Reply #39 on: 13 Feb 2013, 08:57 pm »
Maritan

Because of the oil based Q Damping adjustable seperately in each plane, you can use about anything.  I have used Shures, AT's, Stanton/Pickerings, Grado, Nagaoka, Ortofon and maybe other's I don't remember.  They will all work fine even though the tonearm itself is technically medium mass.  As to your AT's yes it will work fine.  In that TT I have used the AT-71, AT-95e and AT-120e and they all worked fine.  If I remember correctly what Neo said earlier the AT-100e is part of the family that takes any of the styli listed here in Group K giving you plently of upgrade options if you like the basic voicing of the AT.  Just for you information, the two part adjustable overhange headshell, shown in the ad is worth over $40 alone on Ebay and it appears to have a functioning cartridge on it that may give you another option.  The only MC I have ever used in it was the Denon DL-110 which also sounds fine. Don't know anything about the motor in the Kenwood, but the one in the F-6 was among the best of its time.


Jack