Change 555 - to + shift. Can it be done?

[Quacker]

Some gave me a Hitec 555 with a negative shift and I need a positive shift. So I thought to myself that if I were the designer of the 555 I'd design it so that the change from one to the other was very easy to accomplish in production, so how hard could it be in my workshop? I have all the soldering equipment. Does anybody know how to do it?

Q

[DNA]

Ah, the hamster's bladder strikes again...

Not exactly what you want but it may give you some ideas.

http://www.withinc.com/~wwang/HitecMod.jpg

[Quacker]

Thanks DNA, but please keep my hamster's bladder out of this. My guess is that it's in the FM demodulator which comes before the decoder in the link. If all else fails, I'll have to rip my other 555 out of one of my planes and do a careful comparison. I was hoping to avoid this.

Regards from Todd,
Q

PS. Todd loves the Soarstar. He tells me that the seating is much roomier than in the old TM.

[DNA]

Maybe add a shift selector switch to your Tx instead.

http://www.scalesoaring.com/inverter.htm
http://images.honesty.com/cgi-bin/honesty-viewimage.cgi?image=13586594

I have a shift selectable Rx using the same 4015 shift reg. IC,
but tracing the connections on an smt double sided board
is difficult, as you know. This Rx does have a 393 chip
on it. Must be there for the shift selection. Tough to figger
out, without a schematic.

I wondered what you were brewing up for Todd, asking about
100 amp esc's and generic wingo wings. He should be very
comfy with all that extra room, maybe you could even add
something to accomodate his ever expanding bladder.
Any videos yet? (of the flight, not the bladder) ;)