Old Sony Tuner-amp-cassette - UK Vintage Radio Repair and Restoration Discussion Forum

John_BS · 15th Mar 2012, 8:53 pm

A local charity shop was selling this, marked up as needing a "new belt"

It's Sony HST-89, built like the proverbial brick outhouse, and appears to date from c 1978. I've found the service data for the "A" version, but nothing on this actual model. The difference may be just the PA, which for this model is a Sanyo thick-film module STK439 (15+15W), and the "A" version SI1123HD (25+25W).

Does anyone happen to have the information relating to the HST-89?

The Dolby circuitry is discrete, and the tuner is unusual in having FM, LW, MW and a SW band.

John

PS there is a 2-pin link-plug on the back which can be set in one of two positions, marked "ISS". Does anyone know what this might be?

Steve_P · 15th Mar 2012, 9:01 pm

You can get belts here;

http://www.turntableneedles.com/Flat...Inch_p_59.html

There's no download link, but try sending a message here:

http://www.freeservicemanuals.info/e...l/Sony/HST-89/

If you need to! These things do not break down...

Cheers,

Steve P.

emeritus · 15th Mar 2012, 9:09 pm

Is the ISS switch for adjusting the bias frequency when recording to eliminate any beat effects that might arise when recording from the radio? I have seen older cassette recorders with switches for this purpose, some with 3 positions, but don't recall how they were labelled. I never found that altering the setting made the slightest bit of difference, and never experienced the problems that the switch was intended to address.

John_BS · 15th Mar 2012, 11:17 pm

Quote:

is the ISS switch for adjusting the bias frequency when recording

That's the only thing I could think of: in which case, what does ISS stand for?

Steve:

Thanks for the link. In fact, when I took the lid off, the belt was still in position, albeit not perhaps in 100% condition. I took it off and reversed it.

It wouldn't play a cassette, but the capstan was running, so I suspected the pinch roller pressure. However, it turned out that the pinch-roller had seized on its spindle. Clock oil sorted that (but it was a b**** removing the arm without completely dismantling the cassette transport).

John

Andrewausfa · 15th Mar 2012, 11:54 pm

John,

Interference Suppression Switch

Not that I knew or anything, I had to look it up!

Andrew

John_BS · 16th Mar 2012, 8:07 pm

Thanks for that: so it's actually an "Interference avoidance switch" ?

John

Tractorfan · 16th Mar 2012, 11:35 pm

Hi,
It's supposed to stop the recording bias oscillator "beating" with the local oscillator when recording from AM radio and causing whistling noises on the recording. But, as has been said, I never noticed any difference whatever the position of the switch.
Cheer, Pete

IW232323 · 17th Mar 2012, 3:32 am

I have a JVC stereo radio cassette recorder or "ghetto blaster" of the same era and it has a switch labelled Beat Cut Mode. I guess it's supposed to do the same thing although I never noticed any difference either.

15th Mar 2012, 8:53 pm	#1
John_BS Octode Join Date: Dec 2008 Location: Wincanton, Somerset, UK. Posts: 1,780	Old Sony Tuner-amp-cassette A local charity shop was selling this, marked up as needing a "new belt" It's Sony HST-89, built like the proverbial brick outhouse, and appears to date from c 1978. I've found the service data for the "A" version, but nothing on this actual model. The difference may be just the PA, which for this model is a Sanyo thick-film module STK439 (15+15W), and the "A" version SI1123HD (25+25W). Does anyone happen to have the information relating to the HST-89? The Dolby circuitry is discrete, and the tuner is unusual in having FM, LW, MW and a SW band. John PS there is a 2-pin link-plug on the back which can be set in one of two positions, marked "ISS". Does anyone know what this might be? Attached Thumbnails

15th Mar 2012, 9:01 pm	#2
Steve_P Dekatron Join Date: Sep 2003 Location: Bolton, Greater Manchester, UK. Posts: 6,644	Re: Old Sony Tuner-amp-cassette You can get belts here; http://www.turntableneedles.com/Flat...Inch_p_59.html There's no download link, but try sending a message here: http://www.freeservicemanuals.info/e...l/Sony/HST-89/ If you need to! These things do not break down... Cheers, Steve P. __________________ If we've always had it, why is the Car Boot open? You're not sneaking another Old TV in are you...?

15th Mar 2012, 9:09 pm	#3
emeritus Dekatron Join Date: Jan 2012 Location: Brentwood, Essex, UK. Posts: 5,339	Re: Old Sony Tuner-amp-cassette Is the ISS switch for adjusting the bias frequency when recording to eliminate any beat effects that might arise when recording from the radio? I have seen older cassette recorders with switches for this purpose, some with 3 positions, but don't recall how they were labelled. I never found that altering the setting made the slightest bit of difference, and never experienced the problems that the switch was intended to address.

15th Mar 2012, 11:54 pm	#5
Andrewausfa Octode Join Date: Dec 2010 Location: St Ives, Cambridgeshire, UK. Posts: 1,180	Re: Old Sony Tuner-amp-cassette John, Interference Suppression Switch Not that I knew or anything, I had to look it up! Andrew __________________ Invisible airwaves crackle with life. Or they should do. BVWS Member

16th Mar 2012, 8:07 pm	#6
John_BS Octode Join Date: Dec 2008 Location: Wincanton, Somerset, UK. Posts: 1,780	Re: Old Sony Tuner-amp-cassette Thanks for that: so it's actually an "Interference avoidance switch" ? John

16th Mar 2012, 11:35 pm	#7
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,183	Re: Old Sony Tuner-amp-cassette Hi, It's supposed to stop the recording bias oscillator "beating" with the local oscillator when recording from AM radio and causing whistling noises on the recording. But, as has been said, I never noticed any difference whatever the position of the switch. Cheer, Pete __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..." Last edited by Tractorfan; 16th Mar 2012 at 11:36 pm. Reason: Forgot a couple of words

17th Mar 2012, 3:32 am	#8
IW232323 Retired Dormant Member Join Date: Nov 2011 Location: Kent Posts: 7	Re: Old Sony Tuner-amp-cassette I have a JVC stereo radio cassette recorder or "ghetto blaster" of the same era and it has a switch labelled Beat Cut Mode. I guess it's supposed to do the same thing although I never noticed any difference either.