Alesis (DM Lite) Drum kit without kick

Alesis Drum Kit gets a cheap repair.

A neighbour of mine is a talented musician in a local band and also teaches school children various instruments.  Some of his students learn the drums, which is most parent’s nightmare as any notion of a peaceful evening is shattered.  Luckily, electronic drum kits are an excellent way to learn with headphones, while keeping happy parents and neighbours.

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FixItWorkshop, Worthing, November’18, Alesis DM Lite Electronic Drum Kit
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FixItWorkshop,  Worthing, November’18, Alexis DM Lite main drum module

This kit was missing several beats and was hampering learning, so time for a visit to the workshop.  I’m no musical instrument repair specialist, but I thought that the drum kit must use electrical contacts, switches and rudimentary electrical components and I was right.

Two faults were reported; The kick/ foot pedal was intermittently not working and one of the drum pads was hardly working at all, unless you hit it with a sledge-hammer.  Time to see what was going wrong.

First up was the faulty drum pad.  Opening up the back of the pad was simplicity itself, just a few screws held the back to the pad.  Sandwiched between two halves was a sensor, a bit like a piezo flat speaker, similar to the type found in many toys with sounds.  I guess the principle here is that vibration detected by the piezo sensor is converted to analogue variable voltages by the drum kit’s circuitry.  While apart, I noticed that some of the copper detail tracks on the printed circuit board which had a standard 3.5mm jack socket (to allow a connection back to the rest of the kit) had cracked.  Looking again through my magnifying glass revealed quite a bit of damage, probably as a result of many Keith Moon wannabes.  Testing these tracks with my meter confirmed an intermittent fault, so out with the soldering iron, to repair the connection.  Plugging the pad back in, it was ready once again for more drum solos.

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Next up was the dodgy kick/foot pedal.  As the with the drum pad, the pedal would cut out intermittently.  A few screws held the pedal together, so only basic tools required.  See the slide show below for an idea of the construction.

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The fault with the pedal was similar to the drum pad.  Some of the copper detailing around the 3.5mm jack socket had failed and required some careful soldering.  I say careful, as applying too much heat at once would, likely as not, melt the casing of the socket.  One had to take care.

Once soldered, the pedal was much better.  I didn’t get a full 10/10 repair with the pedal since I think there was wear on the kick sensor, but it was an improvement none the less.

Cost of replacement:  £lots.  Cost of repair, my time, two cups of tea and some solder.

 

 

Kenwood Chef Repair

Kenwood repair in Worthing, West Sussex

Smelly Kenwood Chef A901

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FixItWorkshop, Worthing, Jan’17.  Repaired Kenwood Chef A901

This Kenwood Chef developed a nasty little problem. The failure smelled expensive and the Chef even puffed out some smoke when it began to fail, it would operate, but noisily and badly, so it to the workshop it had to go.

It was in decent overall condition and has loads of accessories, so definitely worth saving since a new one is over £300 new.

Since the speed control circuitry is a common failure on models of this age, it seemed sensible to start there.  On this unit, access wasn’t a problem and the issue was quickly diagnosed.  Both capacitors had failed (spectacularly)  and one of the resistors had become weak by about 20 Ohms or so.  Repair kits are readily available online for those who are willing to save these excellent machines, so after removing the faulty components, new items were fitted.

Another little annoying problem with the Chef, was the main drive belt.  It was intermittently rubbing the main plastic body of the unit, making a horrible sound and melting some of the casing (only cosmetic).  The motor mounting spacer had compressed on one side causing the belt to not run correctly.  This was fixed with a small washer to correct the belt’s alignment.

With a little bit of grease, WD40, Brasso, contact cleaner, repair kit and washer, the whole job took a couple of hours (including fettling time) and cost me under £8.  Definitely worth the effort considering the price of a replacement Chef.

Here’s a picture of the new components fitted in situ…

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FixItWorkshop, Worthing, Jan’17.  New capacitors, resistors and triac fitted, fixed!