Flea and other mods to CDi...

[Dowser]

A few weeks later, stress added by death of my father In law and ex-wife heading to CA to take care of thing...and me needing to take care of my daughters in school and unscheduled time off from work. I’m now about ready - done all I can for the car MOT in a few weeks, Tax returns made, ex-wife returns after weekend. I have 4 7220s here to replace those in the Marantz players I butchered (from UTSource in the end - AlieExpress order has been sitting at border point for a month and still not here, so will put a reclaim dispute in - UTSource only a couple of quid more expensive, and reliable tracking ).

Note: see here - looks like the UTSource 7220s are not reliable!

Anyhoo - I listened to Hifi for first time since above post tonight (well, I’ve been listening to radio via FM4). Laverda’s CDi has brought tears to my bastard eyes for last 3 hours straight, I honestly have no idea why I would want more than this...but am still going to try further with my original CDi and further mods. Very carefully now, and with diode isolated bridge-rectifiers!

 

[Wilky]

Keep your chin up Rich and watching with interest.

Dave.

 

[Dowser]

Thanks Dave - my chin remains up

So, update time - I swapped the failed bc550 on CDI #1s Flea out today (it had gone OC base-emitter). Flea working again.

I then did some measuring - this is the 26v supply to the Flea in CDI #1;

This is the same on Laverda's CDI #2;

So I see no problem. I am actually running Laverda's modified Flea in #1, and a more stock one (only input filter modified) on #2. Other than that the differences are in the supply - #1 is full wave with CRCRC, #2 is a bridge rectifier with just a single C.

I have complete disconnected the second transformer for the dedicated 7220 supply for now. Differences between the 2 players are subtle - I prefer Laverda's for dynamics (I suspect, but do not know, because of ALWSR supplies to OP opamps, single crown), but overall prefer my original #1 (original dual crown, full wave supply to modified Flea)...it is just more subtle somehow, lots of little details get picked out.

Now I need to decide whether to investigate differences between the players as they stand (I can easily swap Flea PSUs and Fleas between the players to nail down the differences), or just press forward with further mods to #1. Not going to do anything for a few days...want to see if the Flea transistor fails again first!

One question though - to confirm, there should be no problem mounting transformers like this, right?;

Thanks All! Richard