I dont mind a manual air valve neither. Its just l am trying to make my system wife-driveable.
Ha, 1/4". My whole air suply has about that cross section 
Don, that wuld be great. But a high level in electronic knolidge wuld be nessesery to design a circuit. I hope some good guy is willing to draw it down for us to be able to copy, or buy for that manner…