If you downloaded the book from my previous post you may have seen this.
Mr Carr says the joints need to overlap by 1/4" to keep the RF in. The power is being fed by way of feed through capacitors like these.
He also gives some circuits which are more stable. For high frequencies the cascode is a good choice.
The BF2040 is such a device. The maker declares them to be "unconditionally stable". At 28 cents each and free shipping it's a bargain.
The 2SK2539 Jfet at 3000 for $15 is worth a look also.
I had a small strip of each in an envelope ready to send to NZ and the postmaster said $13.50 was the minimum! Ouch!!
You can buy 48 BF2040s for less than that. Last time I had this happen I simply gave my friend the info and he got a reel of the Jfets for less than I could send them.
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