JTM45 MK IV

garty

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Hi all,

Just like to share this with you. I bought it from a local music store in 1973 aged 18 having joined a band. It was loud and looked great.

The images are post cosmetic 'repairs' taken on a smart phone. Unfortunately, I'm not having much luck uploading other images at the moment, (before repairs and gut shots etc).

Regarding date of manufacture, all the components or style features point to late 1966/67. 1 speaker was replaced before I bought it, reason unknown but the other original speaker,

has T1221 on the frame and 24LL on the gasket, (24th Nov 1966). the pot's have the code 10-6 2M (ohm symbol) LN. Perhaps someone can enlighten me date wise.

Regarding 'repairs', new EC Collins grill cloth was purchased. A new logo and gold piping was fitted. Where the Tolex was damaged or missing i used material from the bass of the cabinet.

A new lower back cover was made and covered with green Tolex and tinted to, as far as possible, match the black/green original covering. Both rear cover fixing screws are not original.

Missing all four feet too. Point me in the right direction for good replicas someone.

Unless anything else was changed from when it left the factory until it came into my ownership then everything else is original and unchanged.

All the controls work as they should, no scratching, the Tremelo speed and intensity work with the foot switch and as far as I can tell, no speaker rub.

After years of being gigged extensively and rattled around in the back of an old Transit van, I feel extremely lucky that it is in the condition it is in regarding the electronics and other

components considering its age and use.

Nowadays it gets warmed up and played through for an hour two pretty regularly at home. I'm not a collector, just lucky to have bought this particular amp all those years ago.

Thanks for looking.
 

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stratburst

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Great amp! Thanks for sharing. Would love to see more pics of the circuit board and transformers. For images I find https://imgur.com/ easy to use. Just upload and copy and paste the bcc link here.
 

garty

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Hi stratburst,
Thanks very much for the info. Unfortunately I am not at all familiar or confident about attempting this. :confused:
My youngest son is popping in tomorrow morning, I'll get him to do it. 🤣
 

TAZIN

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Regarding the potentiometer markings...10-6 (tenth month of 1966; October 1966). The 2M ohm sign is the value (2 Mega-ohms) of the pot and the LN stands for Linear taper.
 

garty

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More photos. Forgot to mention an important detail, serial number - 7423
 

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neikeel

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Pics are a bit blurry (at least on my phone) but it looks great - at a distance!
A Canadian forum member found some really good glides like the originals. I have some the correct diameter and fitting but a bit flatter than originals.
 

garty

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Hi neikeel,
When I Bought the amp it did have feet but I cant remember what they were, I think they just disintegrated. Not casters then? I've always thought they would have been rubber stud type feet. Need to check the witness marks on cab' bottom then.
Sorry about the pic's, I had to resize them. The largest size that would upload is 400x300. Bit of a novice at this i'm afraid.😝
Lots more pic's I'd like to share, if anyone asks, so any advice regarding better quality images would be much appreciated.
 

Ned B

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Hi neikeel,
When I Bought the amp it did have feet but I cant remember what they were, I think they just disintegrated. Not casters then? I've always thought they would have been rubber stud type feet. Need to check the witness marks on cab' bottom then.
Sorry about the pic's, I had to resize them. The largest size that would upload is 400x300. Bit of a novice at this i'm afraid.😝
Lots more pic's I'd like to share, if anyone asks, so any advice regarding better quality images would be much appreciated.
The feet would have been this variety. They turn up every now and then. Our member, Dome Feet 01.jpg Bygone Tones sometimes has them.
 

Dblgun

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I think these have been mentioned as being very similar in the past.

 

neikeel

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I think these have been mentioned as being very similar in the past.

Yep those are the ones!
 

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