Thursday, 30 January 2014

ADVENT 300 Receiver Rebuild - Part 1

I've had this ADVENT 300 receiver hanging around for quite awhile and it's time to get busy on this project. It's not hard to tell it needs a little work.

 Advent 300 receiver

I plan to improve on the cosmetic issues as you can imagine, but also plan to replace other parts to update this classic receiver that came out the year I graduated from high school. Back then I had a tube receiver that I scavenged from a Viking stereo console that an elderly neighbour was tossing out. She had had a tube TV catch fire and didn't trust them (tubes) any more so was going all solid state. She was still sticking with Viking, the Eatons house brand name though. Little did she know that almost 40 years later people still want those tube gadgets. But I digress...

The Advent 300 is still considered to be a great performer and even with its low power of 15 watts per side and kind of chintzy build quality it can rival much nicer newer amps. It's an FM tuner only (even back then AM sucked), and pre and power amp in one case, with jumpers between the pre and power sections so you can use it with other components or add an equalizer if you like.

This one has some stickers and scratches that have taken off the paint, rust damage, and just old parts. The voltage regulator has already been replaced but as far as I know it has had little servicing since new.

Advent 300 case 2

Advent 300 case

The old electrolytic capacitors are all going to be replaced in this project. I will also be trying to clean up or replace some of the fittings, for example the grounding screw and AC jack on the back are respectively rusted and cracked.

I'm going to clean extensively and might "reflow" solder joints. Essentially that means melting the existing solder to ensure that the contact is good. I will replace some of the jumper wires I think too, and clean up the routing in the process. Maybe I will anyway; I will certainly have a look at them and replace if questionable.

Advent 300 inside top

Advent 300 PCB

In the pic above and the one below you can see some of the rust on the case near the power supply and on the RCA connectors. I've actually removed a lot of the corrosion on the RCAs to the left already with a 3M pad and sand paper. The ones to the right are essentially untouched.

Advent 300 RCA jacks

Here you can see the power supply. My first actual real "upgrade" is to replace the 2 large capacitors you see to the left. The stock components are 3000uf at 30volts but I will be using 4700uf at 50volts which is totally acceptable as a component value change for this area.

Advent 300 power supply

In addition to other resources, I am using the excellent website by David Eaton devoted to the Advent 300 as a reference. Thanks David!

I'll be back soon with Part II...

1 comment:

  1. Just found this entry - well done! Keep going, I'd like to rebuild by 300 one of these days...