Good Day All, Well, I took the T-4X off-line here to-day, & set it up on the bench with the top cover removed, exposing the PTO can...
I pondered the ways & means of "sealing" the small gaps between the base of the can & its metal attaching surface, with the intention of eliminating any consequent expansion/contraction effect(s) of the joints upon the oscillator frequency. I settled upon a rather crude, but I think effective, expediency: I simply cut a strip of aluminum cooking foil, and wrapped it around the can base, being sure that there was overlap on the base that supports the "ears" of the can. I then bridged the strip (on both sides) with masking tape, ensuring good bonding along the length of the strip... It's inelegant, for sure, but achieves its end purpose, I think... I put the transmitter on 40-meters CW, and noted the tell tale frequency creep one time---however, the rig had been on for only 10 minutes, barely enough time to warm up. After about 90 minutes, I made a couple of QSOs, and called CQs, all-the-while monitoring myself on my R-4 receiver... I'm happy to report that "...so far, so good." I'll need more time to evaluate the results of all this, of course, but I'm encouraged. Perhaps the ultimate answer lies in operating the rigs in an environment that's warmer than the 49F that the basement was this afternoon! Hi Hi. Certainly, time will tell...I guess I could always place a small incandescent bulb somewhere inside the T-4X to help speed its heating /reaching "operating temperature"---but then that effort would be defeated, in large part, by the cooling fan that extracts air from the 2x6JB6A PA cage! (that rascal keeps the whole inside of the rig cool to the touch). ~73~ de Eddy VE3CUI - VE3XZ _______________________________________________ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
