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I have a radio which required a voltage of 10.8VDC (maximum 13V) with a current consumption of between 20mA (RX squelched) and 700mA. The recommended power supply is quite complex for what it does seen here.
I would like to include a dropper inside the cig lighter plug and I have a number of simple ideas.
One is a 7812 chip the other is three diodes with 0.6 threshold voltage that should drop the max voltage from 14.2 to 12.4 volt.
But two things worry me.
1) If it's so simple why did Yaesu use such a complex method?
2) Will it overheat?
Radio is very old so unlikely to get correct adaptor it's a FT208R so what do other think as to way to reduce car batteries voltage. The ideal would be a switched mode unit that would isolate from car battery and so I could then use a booster from same battery to lift output from 2.5W to 30W I have therefore considered a mains driven unit which I could then plug into my inverter so I have isolation as well as stable voltage.
Again any thoughts?
Considering this from Maplin but wonder about the RF and if it will affect its operation? Any thoughts please.
One is a 7812 chip the other is three diodes with 0.6 threshold voltage that should drop the max voltage from 14.2 to 12.4 volt.
But two things worry me.
1) If it's so simple why did Yaesu use such a complex method?
2) Will it overheat?
Radio is very old so unlikely to get correct adaptor it's a FT208R so what do other think as to way to reduce car batteries voltage. The ideal would be a switched mode unit that would isolate from car battery and so I could then use a booster from same battery to lift output from 2.5W to 30W I have therefore considered a mains driven unit which I could then plug into my inverter so I have isolation as well as stable voltage.
Again any thoughts?
Considering this from Maplin but wonder about the RF and if it will affect its operation? Any thoughts please.