[PCR-1000] pcr1000 power

Sat, 21 Dec 2002 18:10:50 -0600

Frank-
Thanks for the great info on the bottom; I just tossed a few PC power
supplies, dang it!!! I never even thought of using them like this, duhh!
Oh well, I run across them all the time, so now I'll know.
Tom
KE4RXM

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of A10382
Sent: Saturday, December 21, 2002 15:15
To: [email protected]
Subject: Re: [PCR-1000] pcr1000 power

My PCR-1000's (1997 vintage) wall wart is 12V, 1000ma, center hot.  I
can't imagine it's changed any since then...

Common problems:

1) Using a wall-wart supply with incorrect voltage and/or polarity.  On
some devices, wrong polarity is not fatal.  On others IT IS.  Using a
supply that is supplying too high a voltage (i.e.; using a 12V brick on
a 6V device) frequently 'fries' something in the device being powered.

2) Using a 'cheap' wall-wart.  Almost all consumer product wall-wart
supplies are 'cheap ones'.  While they may adequately power the device
in question, manufacturers frequently find the wall-wart as a place to
save a
few pennies.   The wall-wart supplies are almost always 'switching'
power
supplies which are significantly less expensive than a 'regulated'
supply. In order to keep costs down, many (almost all ?) wall-wart
supplies do not have adequate filtering and can be electrically noisy or
even radiate their own 60hZ rf.

3) Using a wall-wart of insufficient amperage.  Using one too low may
result in the device not working properly - and this can be a difficult
problem to diagnose.  Using one with too high an amperage rating (i.e.;
needing 200mw and using a 1000mw supply) may result in the supply being
noisy or without enough current draw to maintain a steady and proper
voltage.  A completely 'unloaded' 12V wall-wart can supply as much as
15V.... just use a dvm and measure the supply at the dc plug without it
being attached to anything.

All three of the above noted 'problems' usually occur when the user buys
a
replacement wall-wart.   Although not usually one of my favorite
suppliers,
Radio Shack has an 'ala-carte' wall-wart display where you select the
appropriate supply (voltage and amperage) and power cord separately.  Be
sure to have the correct voltage, polarity, AND power needs (i.e.;
1000ma). Different plugs can look very similar so it's best to bring
along either the existing wall-wart - if you have it - or the device
itself (or both) .

A number of users did previously post problems associated with using a
replacement supply - mostly of too low a current capability.  If you
have multiple 12V devices, your best bet may be to buy a good bench-top
power supply and power all your 12V devices from it - be sure to fuse
each individual DC lead.  I use an Astron 35 Amp bench-top power supply
to power (in addition to a base transceiver) an additional 6 devices -
works well. It has meters for both voltage and current.

--------
Even 'regulated supplies' (like the one in your PC) frequently require a
load on at least one of it's voltage supplies (the 5V supply for a PC)
in order to regulate the 12V side.  Old PC supplies do make good 12V
bench supplies - but usually cannot be adjusted up to 13.8 needed for a
lot of mobiles.  Usual max is about 12.5V for the 12V side.  A recent
amateur radio magazine has a write-up on recycling old PC power supplies
for use with low power transceivers.

Frank
 ._._.

----- Original Message -----
From: "rtv" <[email protected]>
To: <[email protected]>
Sent: Friday, December 20, 2002 2:46 PM
Subject: [PCR-1000] pcr1000 power

> can anyone verify the wiring of the power connector on the pcr1000
is
> the center conductor positive? (as usual)   i have run into a few on
> other stuff that are not,   i dont want to burn up a new radio before
i
> turn it on!
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