Thank you very much for all of the input. It was extremely helpful, yes the
power supply will be used on a 200 watts ATV repeater amplifier and will be
running 24/7. I have been taking a look at the ARRL handbook and figure that
might be a good starting point but I am going to re-read all of the
information that all of you provided and come up with a suitable power
supply. Once again that you everyone for you suggestions and information.

73's

Craig
"G.Beat" wrote in message
newshp1d.297505$8_6.74360@attbi_s04...
"Paul Keinanen" wrote in message
...
On Mon, 13 Sep 2004 12:36:04 GMT, "G.Beat"
wrote:

Paul and Eric and provided a good background on how to adopt the ARRL
design.
You can substitute the 2N3771 transistor for the common 2N3055 pass
transistor (this is what Astron has done on many of their latest
models).

This suggestion makes sense for low voltage (5-12 V) high current
power supplies, since the worst case current gain (15) has been
specified for Ic=15 A and in general, the typical current gains are
better at very large currents than with 2N3055. Also the Vbe and
Vce(sat) voltages are lower at similar collector currents, thus, the
capacitor voltage can be slightly lower.

[snip]

Please note that the maximum Vce for 2N3771 is only 40 V and since the
capacitor voltage can exceed 40 V and in case of a short circuit, the
emitter is close to 0 V, the Vce could be exceeded. At least use the
2N3772 for the 24 V supply, since the maximum Vce is 60 V. The 2N3055
is also specified for Vce=60 V.

Paul OH3LWR

Yes, I also have the 2N3772 in my parts replacement bin - and have used as
replacements for shorted 2N3055 pass transistors.

w9gb