Clarke and Smith 8812 IF transformer - UK Vintage Radio Repair and Restoration Discussion Forum

PaulR · 4th Aug 2020, 8:41 pm

A while ago I managed to damage one of the FM IF transformers in my C&S radio. The slug just pushed down inside it when I tried to adjust it and I damaged it trying to retrieve it. I have got it sort of tuned but it could probably be better.

My question is would the equivalent transformer from a different FM set work? My gut reaction is that it would but I would just like to check.

vinrads · 5th Aug 2020, 7:54 am

Hi Paul ,it should work is it a FM only set ? Mick.

PaulR · 5th Aug 2020, 8:39 am

No, it also has LW and MW

vinrads · 5th Aug 2020, 9:16 pm

Are there separate if transformers for am/fm . sometimes they are combined in one can , Mick.

AC/HL · 6th Aug 2020, 12:01 am

Can you post a picture of the chassis.

PaulR · 6th Aug 2020, 7:03 pm

Thanks for the replies and apologies for the delay in replying.

I think that it has separate IF transformers. This one didn't make any difference to the AM side.

I will try to takes some photos tomorrow.

Many thanks

PaulR · 9th Aug 2020, 7:28 pm

More apologies for the delay. I have been repairing a first generation Kenwood Chef, it must be the oiliest piece of kitchen equipment ever!

Anyway, here are some photos. Looking at them a substitution might not be so easy as it has both slugs on the top of the transformer

yestertech · 9th Aug 2020, 9:28 pm

Interesting. They look identical to the type Philips used in a lot of sets. I did salvage some ages ago but may have been cleared by now
Any part numbers visible ?

Andy

vinrads · 9th Aug 2020, 10:45 pm

Hi Paul as Andy said the look like Philips transformers , the worst kind to repair.Mick.

PaulR · 10th Aug 2020, 2:15 pm

Hi Andy and Mick

There are no identifying marks on them that I can see. My problem was that the thread or former or whatever you call it along which the slug is meant to screw just allowed it to push right in. It only seemed to be made of acrylic tube or similar and any threads moulded into it would not hold. It is a while ago now but I seem to remember taking it out of its case to be able to push the slug back. Hence my enquiry about replacements from another set.

I have a Cossor 524 chassis but I think that the transformers are those with a slug at each end.

ms660 · 10th Aug 2020, 2:28 pm

Quote:

Originally Posted by PaulR

There are no identifying marks on them that I can see. My problem was that the thread or former or whatever you call it along which the slug is meant to screw just allowed it to push right in. It only seemed to be made of acrylic tube or similar and any threads moulded into it would not hold.

As said, that smacks of Philips, I remember that style when I was in the TV trade.

Lawrence.

PaulR · 10th Aug 2020, 3:13 pm

Hmm it's a pity C&S didn't get something better. Everything else is such high quality

vinrads · 10th Aug 2020, 7:23 pm

Hi Paul are you saying that the former is clear it is just that the slug wont screw in ie the thread gone in the former , if so thread a very thin piece of elastic in the hole then screw the slug in ,knicker elastic used to be the thing round and very thin, Mick.

PaulR · 10th Aug 2020, 8:41 pm

Yes, the former is some sort of clear tube. It looks like celluloid or similar. When I tried to turn the slug it just pushed right in and I had a h**l of a job to get it out again as there was no way in from under the chassis.

The elastic solution is interesting. I am not sure how much damage I did to the former when I extracted the slug but I will investigate it.

Thank you

yestertech · 11th Aug 2020, 2:26 pm

Attached is a very quickly taken picture of the ones I found apologies if it’s inverted as I don’t have software to process it on the phone.
The two top left are marked FM (by me) the others appear to be aerial tuning or a.m. - according to the red writing these came from a Philips B3G 75U
The schematic may indicate whether the FM transformers are suitable ...

Andy

PaulR · 11th Aug 2020, 6:16 pm

Thank you Andy. Could I have one of the FM ones please? Unfortunately schematics of this set are very difficult to come by and I have worked on it without a proper one. I will send you a PM.

PaulR · 25th Aug 2020, 1:51 pm

Andy sent me the transformers. The ones on the C&S are clearly Philips as has been suggested but unfortunately the design is different.

However, I had damaged the slug on mine whilst trying to adjust it because of all the wax applied when new. I managed to extract one from Andy's and used the knicker elastic technique suggested by Mick. I also stabilised the existing tube using heat shrink. This has enabled me to peak the coil and the set is now much more sensitive than it has ever been.

I would be very reluctant to attempt any sort of adjustment on such a transformer again. The combination of the wax which covers not only the end of the slug but the whole of its length and the very fragile former make it more or less impossible to do without damage.

vinrads · 25th Aug 2020, 9:15 pm

We have all been there Paul , well done fixing it . Mick.

4th Aug 2020, 8:41 pm	#1
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Clarke and Smith 8812 IF transformer A while ago I managed to damage one of the FM IF transformers in my C&S radio. The slug just pushed down inside it when I tried to adjust it and I damaged it trying to retrieve it. I have got it sort of tuned but it could probably be better. My question is would the equivalent transformer from a different FM set work? My gut reaction is that it would but I would just like to check. __________________ Paul

5th Aug 2020, 7:54 am	#2
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Clarke and Smith 8812 IF transformer Hi Paul ,it should work is it a FM only set ? Mick.

5th Aug 2020, 8:39 am	#3
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer No, it also has LW and MW __________________ Paul

5th Aug 2020, 9:16 pm	#4
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Clarke and Smith 8812 IF transformer Are there separate if transformers for am/fm . sometimes they are combined in one can , Mick.

6th Aug 2020, 12:01 am	#5
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: Clarke and Smith 8812 IF transformer Can you post a picture of the chassis.

6th Aug 2020, 7:03 pm	#6
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer Thanks for the replies and apologies for the delay in replying. I think that it has separate IF transformers. This one didn't make any difference to the AM side. I will try to takes some photos tomorrow. Many thanks __________________ Paul

9th Aug 2020, 7:28 pm	#7
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer More apologies for the delay. I have been repairing a first generation Kenwood Chef, it must be the oiliest piece of kitchen equipment ever! Anyway, here are some photos. Looking at them a substitution might not be so easy as it has both slugs on the top of the transformer Attached Thumbnails __________________ Paul

9th Aug 2020, 9:28 pm	#8
yestertech Nonode Join Date: Dec 2002 Location: Coulsdon, Surrey, UK. Posts: 2,130	Re: Clarke and Smith 8812 IF transformer Interesting. They look identical to the type Philips used in a lot of sets. I did salvage some ages ago but may have been cleared by now Any part numbers visible ? Andy

9th Aug 2020, 10:45 pm	#9
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Clarke and Smith 8812 IF transformer Hi Paul as Andy said the look like Philips transformers , the worst kind to repair.Mick.

10th Aug 2020, 2:15 pm	#10
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer Hi Andy and Mick There are no identifying marks on them that I can see. My problem was that the thread or former or whatever you call it along which the slug is meant to screw just allowed it to push right in. It only seemed to be made of acrylic tube or similar and any threads moulded into it would not hold. It is a while ago now but I seem to remember taking it out of its case to be able to push the slug back. Hence my enquiry about replacements from another set. I have a Cossor 524 chassis but I think that the transformers are those with a slug at each end. __________________ Paul

10th Aug 2020, 3:13 pm	#12
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer Hmm it's a pity C&S didn't get something better. Everything else is such high quality __________________ Paul

10th Aug 2020, 7:23 pm	#13
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Clarke and Smith 8812 IF transformer Hi Paul are you saying that the former is clear it is just that the slug wont screw in ie the thread gone in the former , if so thread a very thin piece of elastic in the hole then screw the slug in ,knicker elastic used to be the thing round and very thin, Mick.

10th Aug 2020, 8:41 pm	#14
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer Yes, the former is some sort of clear tube. It looks like celluloid or similar. When I tried to turn the slug it just pushed right in and I had a h**l of a job to get it out again as there was no way in from under the chassis. The elastic solution is interesting. I am not sure how much damage I did to the former when I extracted the slug but I will investigate it. Thank you __________________ Paul

11th Aug 2020, 2:26 pm	#15
yestertech Nonode Join Date: Dec 2002 Location: Coulsdon, Surrey, UK. Posts: 2,130	Re: Clarke and Smith 8812 IF transformer Attached is a very quickly taken picture of the ones I found apologies if it’s inverted as I don’t have software to process it on the phone. The two top left are marked FM (by me) the others appear to be aerial tuning or a.m. - according to the red writing these came from a Philips B3G 75U The schematic may indicate whether the FM transformers are suitable ... Andy Attached Thumbnails

11th Aug 2020, 6:16 pm	#16
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer Thank you Andy. Could I have one of the FM ones please? Unfortunately schematics of this set are very difficult to come by and I have worked on it without a proper one. I will send you a PM. __________________ Paul

25th Aug 2020, 1:51 pm	#17
PaulR Dekatron Join Date: Oct 2003 Location: Southport Lancashire, UK. Posts: 3,233	Re: Clarke and Smith 8812 IF transformer Andy sent me the transformers. The ones on the C&S are clearly Philips as has been suggested but unfortunately the design is different. However, I had damaged the slug on mine whilst trying to adjust it because of all the wax applied when new. I managed to extract one from Andy's and used the knicker elastic technique suggested by Mick. I also stabilised the existing tube using heat shrink. This has enabled me to peak the coil and the set is now much more sensitive than it has ever been. I would be very reluctant to attempt any sort of adjustment on such a transformer again. The combination of the wax which covers not only the end of the slug but the whole of its length and the very fragile former make it more or less impossible to do without damage. __________________ Paul

25th Aug 2020, 9:15 pm	#18
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,762	Re: Clarke and Smith 8812 IF transformer We have all been there Paul , well done fixing it . Mick.