deltalight
AK Subscriber
The .33uF film caps look like they are used to "speed-up" and "catch" overload transients for TR09 to trigger the protection circuit. I've added them to both driver boards on the 717 I'm now restoring.
Hello, Welcome to AK, you can buy the components here http://www.mouser.in/; regarding a list, I'd suggest that start a new thread, replace the component with what you got on your amp as reference, and use this thread as a guide on some specifics boards.. Please suggest a site from where I can order
Any good quality film capacitor will be ok in those positions, personally I would use a WIMA film like this:-Hi,
Is it just OK to use the green mylar capacitor for C19, C20, C21and C22 in PCB 2663? Thanks.
Jake
You'd better not - as this will slow up the flashing red protector light considerably - so I think these are off limits for value upgrade The good news is these are non critical - so you can use the plainest Jane 4.7µF, 50V capacitors you can find..Thanks for your recommendation John..
For C606 and C607 (still in 2663), can I use 22uF/50V electrolytics (as a replacement) instead of the original 4.7uF? I ran out of 4.7uF and I still have lots of 22uF available.
Anyone ever mention how much of a time consuming pita it is to get off that glue without damaging the surface of the cards, both amp cards were badly contaminated but came out nice after a long stint of personal attention
Per a previous thread on glue removal, I use toluene sparingly. I tear off a piece of paper towel of the same size as the glue area. Place it on top of the glue, and then drip some toluene on the paper. The glue is now softened after about 3-4 min at which point you can use a small probe to remove it completely with no board scratches. When finished, make sure to remove all traces of the toluene to outside and do not touch the stuff as it gets absorbed through the skin. Rubber gloves might be a good idea here.Have one on the bench this week, first one to get the mods. So far both driver cards responded happily to the upgrades, will note the bias and offset dialed in perfectly and as stable over time as any 717 I have reworked. Will report back as I get through the rest of the amp. Really curious as to tonality changes once I get the tone board redone (which has a dropped signal path issue to track down first). Cool stuff this.
Anyone ever mention how much of a time consuming pita it is to get off that glue without damaging the surface of the cards, both amp cards were badly contaminated but came out nice after a long stint of personal attention
-Lee