BATC 70cm Tx
Posted: Thu Feb 23, 2012 3:12 pm
Hello all,
I have come into possession of an old BATC 70cm transmitter which (I think) was first described in "An Introduction to Amateur Television" in 1992.
The board had lots of intermittent problems, which were due to poor soldered joints.
I repaired these and the transmitter works fine, giving about 4Watts out.
However, on the underside were fitted two home-made tinplate screens, one around the PA module, and one around the bandpass filter.
Does anyone know if these screens were specified in the original project? there is no mention of them in the handbook article, and I suspect the original builder fitted these screens to try and "cure" the intermittent problems of the dry joints.
Anyway, it seems to work without them, although (other than a simple wavemeter) I have no means of testing for spurious emissions.
I do not remember any follow up "Errata" in CQTV regarding this TX, maybe there was, I don't know.
Any info gratefully received.
Thanks
Steve
I have come into possession of an old BATC 70cm transmitter which (I think) was first described in "An Introduction to Amateur Television" in 1992.
The board had lots of intermittent problems, which were due to poor soldered joints.
I repaired these and the transmitter works fine, giving about 4Watts out.
However, on the underside were fitted two home-made tinplate screens, one around the PA module, and one around the bandpass filter.
Does anyone know if these screens were specified in the original project? there is no mention of them in the handbook article, and I suspect the original builder fitted these screens to try and "cure" the intermittent problems of the dry joints.
Anyway, it seems to work without them, although (other than a simple wavemeter) I have no means of testing for spurious emissions.
I do not remember any follow up "Errata" in CQTV regarding this TX, maybe there was, I don't know.
Any info gratefully received.
Thanks
Steve