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NEQRP ColorBurst Transmitter

A number of club members have expressed interest in the original NE QRP colorburst transmitter (so named because of its use of the color burst crystal at 3.579 MHz), and in the "Colorburst Sprints" which were a common event back in the early '90s. The schematic, parts list, and layout are presented here. We have no plans (at this time) to offer a kit; however, parts for the transmitter should be easy to come by, and the transmitter is easy to construct. Perhaps another series of Colorburst Sprints are in our future!

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Comments

I am about to get started on a 79er and wonder if anyone has recommended modifications to the schematic included here. A quick review of the 72 archive gave me a tx/rx switching scheme, but that's the only thing I've seen.

Anyone have a built unit that can be photographed for the NEQRP Gallery?

I'm thinking of building your Color Burst transmitter and using both optional final transistor holes to house two BS170 transistors as used in the Ft Tuthill 80.  The BS170 transistor has very low input and output capacitance and also great switching speeds.  With an epoxied on aluminum plate for a heat sink, the Ft Tuthill rig gets 5 watts output with a pair of BS170s.  In quantities of 100 the BS170s cost 12 1/2 cents apiece.  That's 25 cents a pair.  What do you experts think of this idea for your little transmitter?

Lee, w0vt