EMRFD Message Archive 870

Message Date From Subject
870 2007-06-28 00:15:52 wk73ch 18 MHz Transceiver - Voltages
I want to build this Transceiver - described in chapter 11 of emrfd.
Does anyone know, why all internal voltages must be 10V ? This makes
part procurement (more) difficult.

Thanks

Werner, HB9BNK
871 2007-06-28 00:44:17 Bob Larkin Re: 18 MHz Transceiver - Voltages
Hello Werner,

I have a fondness for the 10 Volt low-dropout regulators. A six-cell
lead-acid battery when at the end of its charge will be just under 12
Volts. Then if there is a little wiring drop and a series diode, you end up
around 11 Volts. The 10 Volts LDO regulators will still be working. That
is why I chose that voltage.

There are many places where lower voltages wok just fine, but other places
the 10 V is convenient. I'm sure that, in general, it could be redesigned
to run on lower voltage.

I have used the dedicated LM2937ET-10 regulators, but I think there are
adjustable LDO devices. Maybe someone on this list has some recommendations
for an adjustable part.

Good luck.

73, Bob Larkin W7PUA

At 07:15 AM 6/28/2007 +0000, wk73ch wrote:

>I want to build this Transceiver - described in chapter 11 of emrfd.
>Does anyone know, why all internal voltages must be 10V ? This makes
>part procurement (more) difficult.
>
>Thanks
>
>Werner, HB9BNK
872 2007-06-28 07:55:36 wk73ch Re: 18 MHz Transceiver - Voltages
Hello Bob,
thank you very much for the precise explanati
873 2007-06-28 14:01:06 Joe Rocci Re: 18 MHz Transceiver - Voltages
The only SE's in our system are Wilkes-Bare, Sparta, and Hazleton
 
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