Goodmans One Ten LH Ch down

[Featherfoot]

Hello everyone. Goodmans 110 as it's been assembled from 4 partially or non working models into (until now) a 100% working model. It took me over a year to realise a childhood dream of owning one of these. A friend's Father had one and to me at least, it looked like something from another planet. I'm talking about the White model of course. I have a small collection of vintage amps including a Cambridge Audio P50 Mk2, Cambridge Audio P110, both from 1975 and the Goodmanstein. All recapped and one or two other upgrades like Blue Alps linear vol pots, uprated input values to accomodate modern cd players etc. The P50 is the best sounding of the bunch. The Goodmans (before I changed the electrolytic caps) was not particularly impressive with a pronounced midrange and surprisingly little bottom end. But the Erie caps were totally knackered. Both the 6300uf cans in the power supply were OC! All the others were way off their values too. Recapping completely changed this fortunately. Still the dominant midrange but by simply adding a couple of db with the eq glues it all together with sweet highs and a fat warm bass. The caps were Nichicon and NOS Roderstein. Anyway, now the LH channel has given out with very little output and very distorted. Interestingly, the distortion is NOT present in the headphones UNTIL you have the speakers engaged also. I am not an Engineer simply a parts changer but I can test components with a DMM. But not in circuit I must add. So I'm a bit stuck. There's only one repairer locally (20 miles away) and he charges £65 to inspect it and a further £65 ph but offers no guarantee of being able to fix it!!So I could spend £130 plus fuel and still have a broken One Ten. Having put so much time and TLC into this project it would be great if anyone has the patience to help me trace the fault and realise my first actual repair. If not, If anyone out there can fix it for me that would be great but I'd like to at least try myself if possible. I followed with interest a few years ago, a Swedish chap on this site who was trying to get his $10 e bay One Ten working and did so with the help of other members. It was this that inspired me to start my own journey with the One Ten. This is the link to his thread: https://www.vintage-radio.net/forum/...d.php?t=171539. So hopefully someone can help me out and I thank you in advance. All the best!

[stevehertz]

I presume by Goodmanstein you mean 'Goodmans'?

If so, the switches on the Goodmans receivers can get very corroded. Apply switch cleaner liberally to all switches but particularly to that seemingly troublesome speaker switch. Then, with the set switched off (power disconnected) operate all switches many, many times. And you may have to do that again and again. See what that brings. If not a result as such, it will at least have cleaned those dirty switches. Best of luck.

[Diabolical Artificer]

Your post is very hard to read, no paragraphs etc. You may get a better response with a shorter, to the point post on the "services wanted" section.

Andy.

[Julesomega]

The tuning in these normally seizes up due to the grease solidifying, so do not try to force the tuning. See separate threads re the use of solvents.
I have a white One-Ten-Stein for disposal, complete with seized tuning, but you can take measurements on your good channel, which should help with fault-finding.
Service data is available via the link at the top of this page.

https://www.service-data.com/section...2134/1/one-ten

[Station X]

Originally Posted by Diabolical Artificer

Your post is very hard to read, no paragraphs etc. You may get a better response with a shorter, to the point post on the "services wanted" section.

Andy.

You're not kidding Andy!

The salient points are these:-

Originally Posted by Featherfoot

Anyway, now the LH channel has given out with very little output and very distorted. Interestingly, the distortion is NOT present in the headphones UNTIL you have the speakers engaged also.

and this:-

Originally Posted by Featherfoot

it would be great if anyone has the patience to help me trace the fault and realise my first actual repair. If not, If anyone out there can fix it for me that would be great but I'd like to at least try myself if possible.

[Ted Kendall]

Originally Posted by Featherfoot

Anyway, now the LH channel has given out with very little output and very distorted. Interestingly, the distortion is NOT present in the headphones UNTIL you have the speakers engaged also.

My money's on the speaker switches.

[Featherfoot]

Thank you for your replies. I apologise for the lack of Grammatical Cohesion but it was going to be a long post and I was concerned with running out of word space.
The first thing I did was to clean all the switches and pots, check fuses etc. But I'll give it another go. This has also given me another idea. The One Ten has provision for two sets of speakers but when I did away with the original 2 pin din sockets (you can't get any decent cable into those) and replaced them with 4 banana sockets, I lost that provision. I will reconnect the second speaker switch in place of the first and see if we still have the same problem. All the best for now.

[Edward Huggins]

It is possible to get a good cable connection into DIN sockets if you use the correct type of DIN plug with screw connectors in the plug.

[paulsherwin]

I suspect the OP is referring to very thick 'audiophile' type speaker cable.

In any event, the conversion has been done now. Please stay on topic.

[Featherfoot]

Hi again everyone.
Yes, the thicker higher quality speaker cables. However, there's a thin line between Audiophile and Audiophool !
Anyway, after carrying out more cleaning and exercising the speaker switches on the One Ten it has produced an unexpected result: a now totally dead LH channel ! I did reconnect the speaker 2 switch but this yielded the same result. I think the problem now may be mechanical as well as electrical. I noticed that the feel of the switches became much more clunky and rather than being flush with each other they now sit unevenly.
This switch gang contains the power off, speaker 1, speaker 2, phones and the two low and high pass filters. I could transplant the switch gang from one of the donor models but of course those switches may not be in the best of shape either and if corrosion is a problem, that may apply to the (hopefully less used) speaker 2 switch also.
I'm happy to do that if anyone thinks it's worth a go and I'm open to any other ideas also. Thanks for reading and all the best.

[Edward Huggins]

Did this problem exist in any way before your removed the original DIN Sockets?

[Featherfoot]

Hi Edward and thanks for your message.
The very first thing I did was remove those din sockets. They can't accept any cable other than you would use to wire your doorbell.
It's been working happily (even the signal strength meter!) for the last eleven months. The speaker conversion is simply soldering four wires when eliminating the second speaker option. I have checked continuity of course and thats ok.
As previously mentioned, I think my only option is to transplant the switch gang from one of the donor models and see where we are. One thing I will do this time is to exercise the switches before installing them - It's less violent and hopefully won't damage them any further. I won't have time to do this until next week sometime. I will report back then. Onwards and upwards!

[majex45]

You say the unit was working properly for 11 months. Did anything precede the failure of the left channel? Buzzing, bangs, flash? Did you plug in or unplug a speaker or did the left channel just spontaneously fade? How quickly, was this gradual or immediate? When switched on or during use?

[vidjoman]

Changing the switches seems a bit drastic as the continuity can be easily checked with a meter. The more you change the more likely to make a mistake and add more problems.

[Edward Huggins]

Originally Posted by Featherfoot

Hi Edward and thanks for your message.
The very first thing I did was remove those din sockets. They can't accept any cable other than you would use to wire your doorbell.

You may be missing my point, The internal DIN socket wiring will be very thin. By using a DIN plug with a very short length of "thin" cable, say 2" to 3", that in turn connected, via a screw type cable connector, to your 79 strand or whatever, there would have been no measurable loss.

[Julesomega]

Originally Posted by Edward Huggins

You may be missing my point, The internal DIN socket wiring will be very thin. By using a DIN plug with a very short length of "thin" cable, say 2" to 3", that in turn connected, via a screw type cable connector, to your 79 strand or whatever, there would have been no measurable loss.

DIN speaker connectors were used on several good quality amplifiers of this period, including the Cambridge A60

[Radio Wrangler]

Don't forget the thin-ness of the wire wound into a coil in the magnet gaps of your loudspeakers. Much vaunted valve amplifiers haven't got the space in their output transformers to be wound with audiophile speaker wires. All together these things constitute an electrical circuit and is affected by the total resistance and inductance. Ohm's law operates here. All the resistances of everything in a trip around the circuit add arithmetically. It's good science and has worked reliably for well over a century. Once you've got your speaker cable resistance small compared to the other items in the circuit, there is very little further improvement available to make, other parts dominate.

David

[Station X]

Originally Posted by Featherfoot

The very first thing I did was remove those din sockets. They can't accept any cable other than you would use to wire your doorbell!

I fed my speakers with bell wire for years, later "upgrading" to two wire mains flex. I couldn't tell the difference.

[stevehertz]

Originally Posted by Station X

I fed my speakers with bell wire for years, later "upgrading" to two wire mains flex. I couldn't tell the difference.

Exactly.

[Julesomega]

The One Ten I have here powers up and sounds very nice with a CD source, I'm not surprised you want to get yours working. The pots and switches all need a good clean, and the tuning capacitor needs unseizing. The VHF tuner is varicap tuned, for which there is a potentiometer ganged on the rear of the Hoft variable capacitor, which arrangement was used on other receivers at this time, including Rank-Arena. This a good sized unit at 23" wide, and a good weight too!

Looking inside the 120 there is no obvious difference, the changes being to the external presentation. That also powers up and I shall be trying that out also.