[PCR-1000] no receive

[Darrel Emerson]

About the PCR-1000 going deaf:
   I still have an early PCR-1000 receiver, and have been following
this list more or less since the beginning.  I think that the business of
third-party
software causing the problem was something put out by Icom as a way of
blaming
someone else. From following this list,  I believe there have been quite as
many 
EEPROM corruptions from people using Icom's own software, as from use of
any third party software - but Icom always denied that.
  I still use the same PCR-1000 essentially daily.
   I had no problems with the PCR-1000 for 6 years, and then one day the
EEPROM corruption struck,  At the time I was using Win98, and had been
doing
so for some time.  Fortunately I had an EEPROM backup, and after EEPROM
restoration 
the PCR-1000 was back on the air, as good as new, in no time.  It's been
running since then
for a couple of years.  Before restoration I made a temporary backup of the
corrupted
EEPROM and examined it.  It wasn't just a single byte here or there, but
essentially all
of the EEPROM bytes had been replaced by Hex#80.
  I never found what had caused the corruption after 6 years of no problem.
 It might
have been Windows interrogating the serial port.  Another theory is that it
was my
power up sequence; I use relatively heavy duty 12 V power supply, and was
in the
habit of leaving the PCR-1000's own power switch turned on, and just
powering up 
or down with the 12V PSU switch.  I could imagine that, particularly after
I turn off the PSU
power, the nominal 12 V output decreases fairly slowly as capacitors
discharge.
You could imagine then that the slowly falling low voltage that's still
applied to the 
PCR-1000 might cause the logic to get into some strange state which could
occasionally
erase the EEPROM.  "Occasionally" could be once in every 2000 power cycles,
or about once per 6 years.  
  This is just a theory.  Since that one EEPROM corruption, I've made a
point of only 
turning on the PCR-1000 at its own switch after my PC has booted up, and
after
the 12 V PSU has been turned on.  Similarly, before powering down, I first
turn off
the PCR-1000 at its switch, before shutting down the PC and powering down
the
12 V PSU.  Since doing that, there have been no further problems - at least
for
2 years or so.  But then, it took 6 years for the first and only problem to
appear,
so I guess I have to wait for a few more years to know if my better power
up and
power down sequence actually makes any difference.

         Good luck,
                     Darrel Emerson.

Original message: -----------------------
Message: 1
Date: Fri, 17 Jun 2005 17:46:21 +0100
From: "Dave Hancock" <dave at davehancock.org>
Subject: RE: [PCR-1000] no receive
To: "'Discussion of PCR-1000 by Icom'" <pcr-1000 at mailman.qth.net>
Message-ID: <20050617164705.B0C97859C28 at mailman.qth.net>
Content-Type: text/plain;       charset="us-ascii"

Hi Chuck,

My unit was deaf on 137mhz but was receiving FM broadcasts ok. I cured the
problem by loading on a copy of a working EEPROM I got from
http://sean.wenzel.net/lists/PCR1000/0413.html. I then used TalkPCR to make
a backup of my original, renamed it and then renamed the downloaded version
so TalkPCR thought it was my backup and restored it. 

This certainly cured my problem and as long as you can make a backup of
your
original you are not going to be any worse off.

Drop me a private mail if you have trouble finding any of the above on the
web and I will send you a copy.

Good Luck!
Dave
Dave at davehancock.org


-----Original Message-----
From: pcr-1000-bounces at mailman.qth.net
[mailto:pcr-1000-bounces at mailman.qth.net] On Behalf Of Chuck Nitsch
Sent: 16 June 2005 01:11
To: Discussion of PCR-1000 by Icom
Subject: RE: [PCR-1000] no receive

Here is what I know for sure... It's not the cable and it's not the
computer.

I have tried to tune both AM and FM broadcast stations, but I get nothing
other than speaker hiss / noise.

I've considered perhaps it's the EPROM, but I don't have a backup.

Has anyone here had the experience of having an Icom go deaf (excluding
white noise from speaker) and subsequently do an EPROM restoration and fix
the problem?
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