DR103 S/N 894

HIWATT amps from the Hylight Electronics era

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waldflote8
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DR103 S/N 894

Post by waldflote8 »

Hello,

Looking for advice please regards this early DR103. I previously gave details of the circuit variation and would like to return it to usable condition certainly,.. but what else ?

Condition is very poor, simply had a very hard life I guess - maybe a good example of how much abuse one of these can take and still function. But time for some action and I am faced with some difficult choices over what to do; certainly re valve (add a bias adjust), electrolytics replacement, good check over and remove the mods,.. but how far to go (especially with the cabinet) ? Apologies in advance, this is not a pretty sight and I hastily add that I am not responsible for any of it :)

How does she sound - fragile, with a lot of hum,.. very much in need of some TLC.

Thanks for all advice.

Andrew
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OldSchoolDave
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Re: DR103 S/N 894

Post by OldSchoolDave »

Shame someone used the serial plate for target practice :( .

Getting the filter capacitors straightened out (complete recap kit) and a fresh set of valves should restore the punch.

It's a worthy project - best of luck.

Dave
...Hey! I played that song when it was new...

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Dr.HI-TONE
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Re: DR103 S/N 894

Post by Dr.HI-TONE »

I would set it right, and accept it for what it is.
I am not one for throwing a bunch of money away on cosmetics.

I used to own #903 that had the same "marshall-like" preamp and it would really scream.
It will be a great amp when un-mucked.
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HI-TONE, when only the best will do.

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waldflote8
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Joined: Sat Mar 15, 2014 5:42 pm

Re: DR103 S/N 894

Post by waldflote8 »

thanks

target practice - yes, I have this vision of someone drilling holes for the jacks from the inside, using a hand drill,.... hope they switched her off first :)

cosmetically - well she is very 'rock and roll' :) I'll try to clean things up a bit and have a close look at the cabinet,.. a lot of weight through the carry handle to be relying on silicon and those screws. Time perhaps for a flight case project.

all the best,
andrew
waldflote8
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Joined: Sat Mar 15, 2014 5:42 pm

Re: DR103 S/N 894

Post by waldflote8 »

Hello again, too many distractions, including a lovely 74 DR103 and cab. which I have been enjoying playing with (bit of a novelty that). But I finally got around to cleaning up #894. FX loop and line out mods removed, filter and bias caps replaced, bit more cleaning up now that those axial filter caps have gone, then look at a bias adjustment mod and some new EL34s. Sadly most of the Mullard pre amp tubes are microphonic or noisy, so will need something there too. Fair bit of carbon on the back of one EL34 socket and they are not the tightest, ..new sockets ?

Advice please, Hiwatts are of course famous for wiring neatness, quality etc. How about these early amps ? apart from the terrible mods, the basic wiring of #894 seems to be quite rough,.. is that normal ? I found when changing the filter caps that the wiring is quite fragile; single core wire breaking and insulation brittle - my aim is functional / reliable and I'll check the continuity of all the old wiring before powering her up,.. just concerned about chasing broken wires every other week in the future. Appreciate the thoughts of anyone who's done a restoration previously. I suppose in a nutshell I am cautious about how far to go when dealing with something that places such a high value on originality. I do not expect to gig with this amp but would like to use it for recording / studio work.

thanks,
andrew
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Dr.HI-TONE
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Re: DR103 S/N 894

Post by Dr.HI-TONE »

because of the condition of this amp, you need not worry about originality.
its too far gone.

Just focus on making it functional and reliable.

all of the talk about the early HIWATTs being built sloppily is unfounded. They were meticulous.

good luck!
http://www.HI-TONE-Amps.com

HI-TONE, when only the best will do.

DR-F
waldflote8
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Re: DR103 S/N 894

Post by waldflote8 »

Thanks, I opened up the 74 amp (will add details of that in a new post) but for the sake of comparison here's a side by side; 70 on left, 74 on right
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74 is un modded and clean, apart from some vandal writing HJ.. 020 on it :D

anyone know why the 70 amp has the extra chassis holes behind the input jacks ?

thanks,
andrew
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Dr.HI-TONE
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Re: DR103 S/N 894

Post by Dr.HI-TONE »

because some of the early PA amps used those for pre-amp tubes.
the same chassis was used for PA's, DR103 and DR504.
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HI-TONE, when only the best will do.

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