Hitachi 8600e sound problem

Hello to all,

I really do need some advice. I have recently bought a Hitachi 8600E retro ghettoblaster and cosmetically it is in really great shape, but now I have noticed while playing either radio/tape or line in (ipod) the sound starts to dip and the quality is poor!

Does anybody have any idea? I really would be grateful for any help.

Many thanks,
Andy.

PS. If I can give any more information I will. Cheers

Hi Andy, welcome to the site.

Congrats on a nice box pickup, always nice to have one in great condition.

A little more information from you would be a great start.....

So, the deck, tuner and line in all work.....great.

But, what do you mean by the sound "starts to dip"....?

Is is diminshing, distorted, fading, both channels, one channel, all sources, made worse or better by.......??

There are many things that can cause poor output and many on this site with massive talent to help.

But, a little more info would be great!

Cheers.

This thread may also be worth reading https://boomboxery.com/forum/viewtopic.php?f=4&t=7103

Hello, thanks for a quick reply, yeah i would say that the sound starts to distort as i increase the volume when it has been on for 5 mins or even less on either radio/tape or line in, if i go between the sources on the funtion switch it gets better for a milli second , sorry yeah on both channels. cheers

Ok, so perhaps a place to start might be cleaning the function select switch, volume pot etc.

I am not sure of your skill level here, be safe first and perhaps search the site before proceeding.

There are many cleaner type sprays available ( ie Deoxit)
The box may need to be pulled apart to gain access to the true internals of the switch and the pots.


Remember ! Open boxes contain potentially live (AC) current and can be very hazardous.

It is also possible that the amp IC may be failing...

Cheers.

Thanks , I have a hitachi 8200 that i have changed the tape belt on before , had that one from new! thats why i bought the trk8600.
so im ok taking stuff apart etc . You mentioned the amp ic whats ic stand for is it replaceable? i will buy some spray what kind do you suggest, cheers again.

Got a philips D8444
Want a sharp gf 777

I've worked on these quite a lot and seen this issue before which is usually down to the function switch needing an ultra clean with contact cleaner.
Make sure you eject the deck door before trying to take the back off. They are relatively easy to work on, just ensure that when removing the back you disconnect the aeriel conenctions first and with the back towards you ease it forward a little more on the left thant he right and sneak your hand in the gap to remove the connector for the LED on the tape deck. If you move the back carefully enough it wont pull off on its own and you can see in the gap to where it is. The rest is plain sailing.
When putting it back together there is a nack to it. Heres the best way. Place the back on its back while holding the top section with the deck door open and lower it into place. This ensures the deck door is on the catch properly and the only thing you have to worry about are ther little switches slotting into their holes.

Thank you for your reply when im able to get some spray( what kind am i looking for) i will try this, had been playing around with it all morning and the sound seems to be getting worse could it be the amp giving out? Ive only had this one about a week cheers

You can buy contact cleaner from maplin. usually with chips it's either working or not. A clean is the first thing to try.

will do mate cheers!

andyt2256 said:

Thanks , I have a hitachi 8200 that i have changed the tape belt on before , had that one from new! thats why i bought the trk8600.
so im ok taking stuff apart etc . You mentioned the amp ic whats ic stand for is it replaceable? i will buy some spray what kind do you suggest, cheers again.

Got a philips D8444
Want a sharp gf 777

Click to expand...

IC stands for Integrated Circuit, can be replaced but is soldered to the board - many pins.

IF you can source one.....

Hi again, I have been messing around with my trk8600e since i have been home and i have a bit more information, While on radio i have noticed that if i keep the volume very low on fm the stereo indicator is illuminated but when i increase the volume the stereo indicator goes off and the sound starts to distort again, It is still the same on tape or line in though very distorted and poor quality Hope this can help a bit more on the solution. Thanks.

sounds like something a bit more than a cleaning usally the cleaning of the funtion and record bar switch corrects a lot of the problems ,,, but that sounds more like voltage which could be a couple of shorted caps or some other componet that might be going bad or even a bad solderjoint

I have never owned that model but have seen lots of Hitachi examples where they used early 2-sided board designs that were very poorly done. The top side traces deteriorate, they even printed resistors on with carbon paint. And the component density is very tight and capacitors prone to deterioration.

Like Ramon said, this sounds like it's probably something beyond the easy cleaning stuff. Time to call in a tech or maybe sell this to someone else that has the skills/ability/equipment to troubleshoot/fix this.

Thanks for all your replies, Have also noticed the vu meters flicker nice with very low volume but on increase they are motionless, when on tape playing it is starting to cut out now on volume increase aswell ! think i am going to ask for a refund and shell out for the one i wanted all along the sharp gf 777

Clean the small microswitch connected to the input selector. It is a power switch and very common problem. I have already repaired two or three Hitachi models with this same problem.

Hello there, when you say the input selector is that the function switch? would it be best to clean it with some contact cleaner ? It looks like i will take the back off and have a go myself , Thank you very much for your reply!!!!

andyt2256 said:

Hello there, when you say the input selector is that the function switch? would it be best to clean it with some contact cleaner ? It looks like i will take the back off and have a go myself , Thank you very much for your reply!!!!

Click to expand...

If you haven't cleaned the switches and contacts first, do that and then reassess.

andyt2256 said:

Hello there, when you say the input selector is that the function switch? would it be best to clean it with some contact cleaner ? It looks like i will take the back off and have a go myself , Thank you very much for your reply!!!!

Click to expand...

Yes i mean tje input selector. It's better to clean all contacts and switches at the same time when the box is open.

I use this:

it includes some kind of oil and works VERY well. There are other similar products, just use something with lubricant.

when you say use something with lubricant and i have read wd40 is no no would STP silicone spray do the same as it drives out moisture not that im a rep i just have a tin lol cheers daz

the real problem is oxidation and arcing inside a switch,,sometimes a bit of deoxit or contact cleans will clean it but if too much piting or green oxidation residue on the surface, which at times the only way is to desmantle the suspect switch and give it a fiscal cleaning which not everyone will delve into especialy if you dont have enough knowleage about electronics... but have you ever taken a dc powersupply and touched the red and black cable you will see a spark and depending on voltage it will be greater thats exactly what happens to all those power function switches that over the years of on and off the spark starts erroding at that piece of metal after all these years sometimes its not as bad which by the looks of some boxes they still function till this day with no issues but others will always have problem that will need more attention so no to wd40 or anything else that is not used especially for electronics and very sensitive equipment