June 2011 - Amploft

Viva Component Indepencia

Where to buy electronic components?

Electronic components seem to be consigned to history. Maplin is now more of a toy shop, radio shack has long since gone. Thank goodness for small independent shops says one amp repairer!

I occasionally use the big online stores like RS and CPC Farnell but why do they charge £5 for a resistor? I just don’t get it.

However on ebay I find lots of little shops being operated from home selling resistors individually for a reasonable postage. It’s an amazing change for me. In five years ebay has gone from a novelty to neccessity and I would never have thought it possible.

Another of my favourite shops is bitsbox very reasonable postage and wide range of stock also helpful with it. Thoroughly recommended and I am sure that there are more just like it.

Recently I needed to buy a neon lamp and found it very hard matching something that was only made 20 years ago. Increasingly disposability will mean that availability will continue to decline.

Yamaha G100 II Guitar Amp Head

I really like this amp – it’s big. Big knobs, big sound, big heavy wooden box and transformer, enormous capacitors like cans of red bull. From the outside it looks like it is stuffed full of vacuum tubes – so what’s not to like?

Inside it is really well put together neat wiring looms, circuit boards and plenty of cooling. I would definitely like one of these of my own but maybe a combo would be handier for me.

Play wise it has two channels a straight clean channel and a fuzzy pre-gain channel. For me there are way too many tone knobs to play with including a parametic EQ which I could mess about with forever and never learn any of my songs. Also this amp as a lovely reverb sound and I think these amps would be great in a rock n roll set up as they are surely loud enough for most gigs.

This one just had a little problem of a loose transformer. Strangely the transformer, which must weight several kilos, is held in by four skinny little screws. Quick fix for this sort of thing is just to tighten them up every twenty years. If you don’t then it could be kind of a mess. What I also add is a little threadlocker paint that keeps the nuts tight even in the event of a little vibration which is inevitable on a transformer.

Also the little neon lamp had a broken lens. Easy enough to replace although it turns out hard to find a one big enough so I had to improvise a reducing bezel with a washer. Not brilliant but enough to keep this amp going.

HH IC 100

This HH IC 100 came to me with filter capacitors dried up. Simply replaced with high quality modern ones from CPC electronics. Fortunately they were roughly the same size so I was able to use the existing rivet system for keeping them in place. However solder tags are hard to come by these days and I had to make my own from tinned copper wire wrapped into a loop and soldered onto the PCB mount of the electrolytic capacitor.

Also found that the smaller filter capacitors that smooth the low voltage (+/-15v) power supply that is used for the pre-amp supply rails had dried up blue paper on them. This seems to be a popular problem for this range of amps and maybe caused by the caps being so close the high wattage resistors nearby which run warm.

The sound of this amp is not particularly remarkable and in fact seems a little quiet compared with the other HH amps looked at recently. I am not sure what the reputation is with these amps.

UPDATE: These amps are a little quiet when the switches are old and knackered. They switch the sound between studio and stage volume and the difference is not surprisingly quite a bit. It’s a little lesson really checking each switch out carefully and giving a it a firm wobble to see if there are any bad connections.