8mm Forum: Soundless Chinon

This is topic Soundless Chinon in forum 8mm Forum at 8mm Forum.

To visit this topic, use this URL:
https://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=013076

Posted by Trevor Adams (Member # 42) on September 03, 2019, 12:17 AM:

Just aquired a Chinon DS300. It shows a nice picture but the only sound I can get out of it is a high pitched whistle.Open to ALL suggestions! [Confused]

Trev

Posted by Maurice Leakey (Member # 916) on September 03, 2019, 02:55 AM:

Trevor
I have just looked at my log-book as I had a Chinon Sound 7500 with no sound.
I see that the problem was rectified by replacing two faulty power capacitors, 1000uf(microfarad) 50volts. A new 2 amp fuse was also needed.

Posted by Melvin England (Member # 5270) on September 03, 2019, 03:25 AM:

Trevor - Notwithstanding Maurice's sound advice (no pun intended), I had a problem like this with my projector. I simply pressed the record button for a second or two (no film in the projector)...released it... job done!

Maurice - If my method made you cringe after reading this, my sincere apology!

Posted by Maurice Leakey (Member # 916) on September 03, 2019, 04:55 AM:

Every little helps (thanks to Tesco). [Big Grin]

Posted by Trevor Adams (Member # 42) on September 03, 2019, 06:33 AM:

Update.'tis the bewitching hour at Auckland(and the rain is pelting down!).I tried the "RECORD' button to no avail.The high pitched squeal just got louder. So,looks like capacitators next ,thanks Maurice. I've had three of these machines and this is the first to remain 'silent".It has been reasonably well stored.I had to clean rust off the lamp pins to get light.Having done that it gave a nice steady picture.Maybe someone has a service manual that mentions the high pitch squeal????Thanks chaps.

Posted by Maurice Leakey (Member # 916) on September 03, 2019, 10:41 AM:

Trevor
You can get a printed repair manual (and also an operator's manual) from Oldtimer Cameras here in the UK.
I use this company very often and can thoroughly recommend them.
https://www.camera-manual.com/model.php?modelid=2587

Posted by Winbert Hutahaean (Member # 58) on September 03, 2019, 11:31 AM:

Hi Trevor, I bought all your 8mm films back in 2011... are you returning now? Good to know that...welcome back! 😄👍

Posted by Trevor Adams (Member # 42) on September 03, 2019, 07:55 PM:

I've just sent off for a copy of the repair manual thanks Maurice.The projected picture is sharp and steady.Had a listen with headphones but no sound (save the high pitch whistle)is getting through at that level.

Posted by Steve Klare (Member # 12) on September 03, 2019, 08:18 PM:

Other than the ones I've been able to kill by working switches and jacks, the whistles I've had from my machines have been because some amplifier has gone sour.

An amplifier "magnifies" the signals going through it. If the output is fed back to the input, the signal can grow all by itself and the thing doesn't need an input to make an output anymore.

When this is intentional, it's called an "oscillator". When it's not, it's called "instability"! (It's also what happens when somebody with a microphone stands in front of his own speaker.)

I developed a whistle on track 2 of my ST-1200HD. I found the only way to tame it was replace the pre-amp IC for that track.

Posted by Trevor Adams (Member # 42) on November 04, 2019, 07:32 PM:

Reckon you are right Steve!

UBB.classic^TM 6.3.1.2