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5678 Breadbox

Bigger than a breadbox?  Well not really,  This set was not only a design marvel for even the handiest wood crafter, but the unique tube proved to be a very challenging circuit.  As far as the circuit, I owe two people all the credit that could be offered.. Dan Petersen and Mike Peebles.  They helped me put all the components where they belonged and put the values what they needed to be.  After dozens of e-mails back and forth, a few laughs from them at my attempt, this is what we came up with.  I literally tried different values for every component, tested and tried, what you see here is by far  the best values for the grid and tickler coil.  The main tuning capacitor is a 6 gang with all the gangs shorted.  Total capacitance is actually 435pF and the coil was designed around that figure.  After the circuit was designed and built, I had to figure out how I was going to package the whole thing.  I wanted something different and something that no one had done before.  The roll top seamed right.  It took about 2 weeks in the garage to put it all together.  The performance of this little tube is fantastic!  I was able to bring in WCBS 880 NY (500 mi.) and 870 WWL New Orlands (750 mi.)  That's only a 10kHz separation!  I am not going to include any dimensions or specifics on the components but if you want them, please email me and I will be glad to send you anything you want.