[Milsurplus] inverter whine from prc10 and bc611 battery adaptersand prc10 150 hz tone mod

[JEFF CICCONE]

folks

i broke down and bought off epay inverter power supplies from the guy in italy.


the bc611 is 2 cylinders fastened together uses 1 d cell for filament voltage and 3 d cells feeding the inverter part. it fits in nicely in the battery compartment. there is a noticable whine in the transmit audio. receive has a slight whine but nothing so bad that the receiver cant hear


the prc10 power supply uses a 6v sealed lead acid battery. also a whine but not too bad and i can live with that


anyone have ideas on filtering? i think its just picking it up thru the b+ line. add a filter cap (what size) to ground?  or some kind of choke is series w the b+?  


finally any ideas on adding 150hz tone to the transmit audio on the prc10? i cant count on everyone doing the breck k4che ''old squelch'' mod at the meets



let me know. thanks


jeff kg2bz
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.qth.net/pipermail/milsurplus/attachments/20170417/1c61b1a3/attachment.html>