Free Harman Kardon 430

[Sir.Byrd]

I really didn't want to, but I went to my local block party.
We brought our cute Siamese kitten Steve and he brought a lot of attention especially when he met a neighbors dog. It didn't end up being all that bad, Although I didn't eat much food. I talked to my direct neighbor and my step dad was actually already talking to him about my vintage stereo stuff, my neighbor then went on to say that he had an old receiver in the basement that hadn't been used in years. He said that it was really scratchy and that was all he remember about it. Then he said that he thought it was Harman Kardon. My jaw dropped as I knew that I could easily fix it! (It ended up needing a thorough Deoxing and a new internal fuse, but I had two handy so I replaced them both)

Now that it is working perfectly I have a dilemma, should I give it back to him because it probably sounds better than what he is currently using? Or should I keep it and either use it as my main or sell it to a friend or via Craigslist.


His name is Steve.

[Sir.Byrd]

Meow meow.

[Robisme]

Ask him if he wants it back. I doubt he will. Than do what you want with it. If your not going to use it, and he doesn't want it, give it to someone that does.

Rob

[Fast_Eddie]

I don't know, he gave it to you. If you saw him you might tell him that you were able to fix it for next to nothing and ask if he was sure he wanted to give it away. He probably is glad to have one more thing out of the house. I wouldn't go out of my way to try to return something that was given to me.

I got a Velodyne subwoofer from a neighbor. It just needed a fuse. He was moving and glad to have that "broken old crap" out of the house. I never feel bad about it when I use it.

Take care,

Ed

[terra1]

He gave it to you because he thought you would appreciate it.

I'm not sure what he would think if he knew you sold it but maybe you got the impression maybe he knew you would anyway if the talk centered around your vintage dealings.

So I would agree its up to you to decide what works for you.

I would give it a chance to work it into your rotation and see if it might be better than some of your non-working projects before you start counting dollar signs though. ;)

[Sir.Byrd]

So I am listening to this, and there are a couple of anomalies... when you turn it on instead of a relay clicking on (there isn't one) it sort of builds up power (or sounds like it) and then does this annoying whine into probably like 10khz out of both speakers but not the receiver.
I can clean the switches to see if that would help, I can only get to the pots for the knobs from the top, so I'll have to take off the bottom plate later.
Alright.
Cool.

[terra1]

Hopefully it's just cleaning but here's a thread I saw earlier on HK hum and hiss. There might be more stuff if you search.

http://www.audiokarma.org/forums/showthread.php?t=164874

[Robisme]

If it's like the 730 I had, it has a slow start circuit instead of a relay. Sounds like a noisy transistor in said circuit.

Rob

[shimniok]

Congrats on the acquisition. Let me be the first to say (regarding the receiver):

:worthless:

:D

I saw the pic of the kitty -- cute one at that! :D

Sounds like he gave it to you -- in which case his assumption almost certainly is that you'll fix it and then either enjoy it or sell it. He might want to know what ever became of it. Did it go to a good home (yours included)? Did it ever get fixed. A thank you after it is all patched up might be good...

If he wanted you to fix it for him, he would've asked. :D

Best of luck in the repairs!

Michael

[Brian]

In a case like this, I recommend buying the guy a six-pack as a thank you or maybe a nice wine or something he may enjoy. A year or so ago the local stationary store had a sale on pen sets. Scheaffer pen and pencils and Cross fountain pens for something like $5 per set. I grabbed a dozen sets and when someone does something I appreciate, I flip them one of the sets. Come to think of it I think I'm down to 1 of each; time to go shopping again.

[terra1]

You also may want to start another thread asking for help or tips on this.

Does the whining go away when it warms up?

[Sir.Byrd]

If it's like the 730 I had, it has a slow start circuit instead of a relay. Sounds like a noisy transistor in said circuit.

Rob

Hmm, it that cause I guess it sounds normal... it's not really that bad, but it was just hard to describe. The dual power supplies are cool.

[Sir.Byrd]

You also may want to start another thread asking for help or tips on this.

Does the whining go away when it warms up?

The whining stayed after playing it for about 3 hours.

[tensleep]

You could always give your neighbor the cat - maybe the hiss will go with it. Now, if the hum goes away, too, you will want the cat back so you can go on The Tonight Show. The high-pitched whining, in my experience, is usually caused by coworkers.

I think a 6-pack or a good ceegar, maybe a nice CD, would be in order. I always love gift certificates to the movies, too.

[ecluser]

If you tune the tuner between two stations, muting swith to ON, and the selector switch to AUX, is the hiss present when the volume control is at minimum ?

[terra1]

The whining stayed after playing it for about 3 hours.

I would probably watch it to see if it igets hot.

I don't know much about the cause but if you make a separate thread then maybe it will catch the eye of more techs who could walk you through the troubleshooting.

And maybe eventually get a service manual and do a bias/offset adjustment too if it allows. Saw some free service manuals but they are in .rar format. Maybe someone will have it in pdf.

[Sir.Byrd]

terra1:
it did not get very hot at all, playing at moderate levels.
I'll clean all the buttons to make sure, it got to late last night and I still haven't taken off the bottom cover.

[terra1]

terra1:
it did not get very hot at all, playing at moderate levels.
I'll clean all the buttons to make sure, it got to late last night and I still haven't taken off the bottom cover.

check ecluser's post. He was the one who helped on that other thread.

Looks like you got the attention of someone who can help.

[Sir.Byrd]

Found the problem! Another fuse was burnt out on the bottom.
Man, these spare 3A 250V fuses are really coming in handy!!!
The FM muting/aux trick didn't work, but I think that the muting adjustment on the back was probably messed with. I deoxed the buttons and power switch. I am just going to let it sit and dry for a little bit and play er again.

[Sir.Byrd]

Okay, so updates.
That didn't seem to fix the problem, but I've noticed that the ringing only happens in AM and Aux inputs. FM, FM stereo, and phono seem to be unaffected.
Also, hi-cut cuts down the ringing, just like the ringing was part of the music, Treble control can turn the ringing up, but not down. Volume control does not have and effect on the volume of the ringing though, it stays at a constant even when the volume is all the way down.

Can anyone diagnose the problem?

[Sir.Byrd]

Swapping for better cables significantly reduced the volume of the ringing, but its still there...
I'll try deoxit on the RCA inputs. The ringing goes away when I unplug the rca cables from the receiver, but leaving the settings on the receiver the same.

I'll try my minidisc deck, and a different tape in my tape deck.


Here is the only picture I could snap before my camera ran out of magic juice (long dead batteries)

[Sir.Byrd]

Contour feature is really nice, its like loudness but less boomy, lessens until it has no effect past 12 o'clock.

[terra1]

Okay, so updates.
That didn't seem to fix the problem, but I've noticed that the ringing only happens in AM and Aux inputs. FM, FM stereo, and phono seem to be unaffected.
Also, hi-cut cuts down the ringing, just like the ringing was part of the music, Treble control can turn the ringing up, but not down. Volume control does not have and effect on the volume of the ringing though, it stays at a constant even when the volume is all the way down.

Can anyone diagnose the problem?

Respond to ecluser's post. See if you can get a dialog going. He offered to help and mentioned the Aux thing.

[terra1]

By the way, you don't owe the neighbor an offer to return it. I'm sure he knew what he was doing.

But I think you do need to show some respect for his gift by giving it a good audition before even thinking about selling it. I'm sure he got a lot of enjoyment out of it that maybe you could coax out of it too.

If it doesn't work out, that way when he asks you about it you can answer honestly and without guilt or moral dilemma.

It's a well respected piece of gear by any standard if it is in good shape.

Worthwhile keeping for awhile especially if you put in time with people here and getting their advice to help you fix it.

[Sir.Byrd]

I think I'll keep it for now, I'd never sell it until I can get it 100%, and usually seeing as how craigslist is... I'll be holding it for someone for a month or so, and then never repost it.

[Sir.Byrd]

If you tune the tuner between two stations, muting swith to ON, and the selector switch to AUX, is the hiss present when the volume control is at minimum ?

Doesn't help, the whine is always on AUX and AM radio no matter what anything else is set to (besides speaker selectors of course)
I adjusted the muting to be as muting should be, and it still doesn't work...

[ecluser]

I asked to tune between station with muting ON to rule out the possibility of leakage through the selector switch. I got the answer.

Download the manual for your 430 from this link:

http://www.audio-circuit.dk/

If you can't open the file, send me your email adress and I will send you a PDF

If you have noise with the volume all the way down, I suspect noise is coming from the supply.

Remove C503 and C504, on the tone board. This will disconnect the amp from the input.

In this condition, do you have too much noise?

See you later.

[Sir.Byrd]

I asked to tune between station with muting ON to rule out the possibility of leakage through the selector switch. I got the answer.

Download the manual for your 430 from this link:

http://www.audio-circuit.dk/

If you can't open the file, send me your email adress and I will send you a PDF

If you have noise with the volume all the way down, I suspect noise is coming from the supply.

Remove C503 and C504, on the tone board. This will disconnect the amp from the input.

In this condition, do you have too much noise?

See you later.

At first I did tune between stations with FM muting on, but there was still static, so I adjusted FM muting so there was no static between stations and tried the trick again, no dice.

[ecluser]

I think I was not clear, pardon me.

It is common to ear the tuner when the selector switch is in another position, say in AUX, when the signal level to the other source is very small (soft passages or silences), and there is a strong signal from the tuner.

Usually this comes from leakage in the selector switch. Some receiver shut down the tuner, or short their output (frequent on Marantz), when you select another source to prevent this. In other receivers the tuner is always live, they let you listen to a CD and record from the tuner at the same time (frequent on Yamaha and many others).

From your post #26, I understand that this is not a leakage problem and you have noise when you select the AUX input, and no signal from the tuner (tuned between two stations and muting switch to ON). Is it exact?

From your post #21, swapping for better cables... it may be a RF interference problem, picked up by the cables.

If nothing (no wire) is connected to the AUX input, do you hear this noise when the AUX is selected?

[Sir.Byrd]

If no wire is connected to the AUX then the noise is still there, but if the cable is connected to the back with no source connected to it on the other end there is noise.
I'll try with yet another cable, but I didn't have a problem with these cables ever before.
I've also tried it on the tape inputs.

[ecluser]

So I am listening to this, and there are a couple of anomalies... when you turn it on instead of a relay clicking on (there isn't one) it sort of builds up power (or sounds like it) and then does this annoying whine into probably like 10khz out of both speakers but not the receiver.
I can clean the switches to see if that would help, I can only get to the pots for the knobs from the top, so I'll have to take off the bottom plate later.
Alright.
Cool.

Open the top and bottom, and clean pots and switches with good contact cleaner in first instance.

If it doesn't help, we will see.

[Sir.Byrd]

Open the top and bottom, and clean pots and switches with good contact cleaner in first instance.

If it doesn't help, we will see.

I did, didn't help.
I'm going to look to see if anything is messed up on the input board, and I'll clean the contacts of the RCA connections.

[ecluser]

Can you give a good description of this "noise" ?

In post no 6, you talked about "annoying whine".

In later post you talked about "ringing"...

When you say it is not present on AM or Phono, is it because it is weaker (when you select Aux input) than the normal noise on the AM or Phono, and the abnormal noise is masked by the noise from the phono preamp, or is it clearly stronger on the Aux input than the normal noise from the phono preamp? In other words, is your receiver noisier on the Aux input than it is on the phono at the same volume setting?

By the way, since you reported this noise with no wire connected at the input, I don't think cleaning the RCA connections will help.

[Sir.Byrd]

Can you give a good description of this "noise" ?

In post no 6, you talked about "annoying whine".

In later post you talked about "ringing"...

When you say it is not present on AM or Phono, is it because it is weaker (when you select Aux input) than the normal noise on the AM or Phono, and the abnormal noise is masked by the noise from the phono preamp, or is it clearly stronger on the Aux input than the normal noise from the phono preamp? In other words, is your receiver noisier on the Aux input than it is on the phono at the same volume setting?

By the way, since you reported this noise with no wire connected at the input, I don't think cleaning the RCA connections will help.

I guess I wasn't exactly clear, I couldn't really describe the noise that the receiver makes clearly, its a ringing or whining high pitched sound into both speakers. The volume of this sound is constant regardless of the volume.
It only exists when it is on AUX or AM radio. When you switch it to AUX with a source it makes the sound. When you switch it to AUX with a wire connected but no source on the other side, it still makes the sound. When you switch it to AUX without a wire, it makes no sound at all.

Does that make sense?

[BrocLuno]

Well if the volume is constant, it has to be an oscillator leaking through to the output stage and not going through any gain control? Could be coming though a filter cap? Could probably find it with a scope or even a freq meter if you can find the trace feeding the signal?

[Sir.Byrd]

Well if the volume is constant, it has to be an oscillator leaking through to the output stage and not going through any gain control? Could be coming though a filter cap? Could probably find it with a scope or even a freq meter if you can find the trace feeding the signal?

That totally went over my head...
but sometimes (although I may be crazy) the sound does sound like it is "oscillating"

[ecluser]

If you remove the bottom steel plate, and you bring one finger close to the tone board (the one close to Bass, Treble, Balance, Volume knobs), I guess you have the same caracteristic noise but louder. Is it right? Take care not to touch the circuit, it could be harmful for your speakers.

[Sir.Byrd]

I refreshed some of the week looking soldered connections last night, and I deoxed some connections that I think would help, and the sound is still there, but its a lot quieter.

[Sir.Byrd]

I took it farther apart today, and clean all the switches more thoroughly, as well as cleaned the bass and treble controls, balance, volume.

The sound is almost gone, so much so that if you didn't know it was there in the first place you wouldn't notice it. I think it's just a pot I maybe didn't clean all the way, I'll let this dry and then try again and see if I can reduce it more!

[Fletch]

A very nice find. Looks a lot like my 330c. Looks like you found the issue though. Enjoy it, I know I enjoy mine.

[Sir.Byrd]

A very nice find. Looks a lot like my 330c. Looks like you found the issue though. Enjoy it, I know I enjoy mine.

I happen to have a 330c too.