Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site pitt.UUCP
Path: utzoo!watmath!clyde!cbosgd!ihnp4!mhuxn!mhuxr!ulysses!gamma!epsilon!zeta!sabre!bellcore!decvax!genrad!panda!talcott!harvard!seismo!rochester!cmu-cs-pt!cadre!pitt!hoffman
From: hoffman@pitt.UUCP (Bob Hoffman)
Newsgroups: net.analog,net.audio,net.ham-radio
Subject: Re: Electronics wearing out
Message-ID: <1005@pitt.UUCP>
Date: Wed, 19-Jun-85 11:20:11 EDT
Article-I.D.: pitt.1005
Posted: Wed Jun 19 11:20:11 1985
Date-Received: Sun, 23-Jun-85 04:16:02 EDT
References: <2663@decwrl.UUCP> <508@edison.UUCP>
Reply-To: hoffman@pitt.UUCP (Bob Hoffman)
Organization: Univ. of Pittsburgh Computer Science
Lines: 50
Xref: watmath net.analog:340 net.audio:5167 net.ham-radio:2868

Judging from the direction this discussion has been taking, I think
the point of the original note was lost.  I don't think any of us
object to batteries being used in radios and the like to store
transient information.  What's being objected to here is the use
of a battery-powered CMOS RAM _i_n_ _p_l_a_c_e_ _o_f a ROM for storing
the "permanent" part of the controller's memory.

In particular, Icom markets a series of radios with this sort of device.
The IC-R71A receiver, the IC-751 HF transceiver, the IC-271 144 MHz
transceiver, and the IC-471 440 MHz transceiver all use a
microprocessor based controller.  Each radio, of course, has different
operating parameters, such as frequency range, modes, etc.  Therefore,
the operating system must be different for each microprocessor.  Now,
rather than using a ROM to store the operating system, they chose to
use a CMOS RAM backed up by a lithium battery.

If the battery should become disconnected, or if it should go dead
(claimed life: 6-7 years), the RAM loses its contents, and the radio
becomes completely useless.  Unlike older receivers that used a
tuning capacitor to adjust the local oscillator frequency, it is now
done digitally with a voltage-controlled-oscillator and a digital
counter in a feedback loop.  Without the microprocessor running, the
digital counter no longer works and the radio ceases to function.
Completely.  As one person mentioned earlier, it becomes a ~$700
doorstop.  The only repair is to send the radio (maybe just the RAM
module, I'm not sure) back to Icom to have the battery replaced and
the RAM reloaded.

What will happen when Icom decides to discontinue support for this line
of radios?  I tend to keep my radios a long time.  I dread the thought
of being helpless to prevent these units from failing.

If I were more adventurous, I would build a circuit to dump the contents
of the RAM into my computer and save the result on disk.  Then, I could
either reprogram the RAM myself, or burn some ROMs to replace the whole
module.

What could have been Icom's motivation for doing this?  Are they really
out to screw the public by making the radios obsolete before their time?
Could it be cheaper to manufacture this RAM module than a similar ROM?
Do I sound bitter?  You bet.  I own an R71A and a 271H and I think they're
excellent radios.  Really first class.  Except for their built-in
obsolescense.  I had planned on getting a 471 next year, but am now
reconsidering.

Tnx for reading & 73,

-- 
Bob Hoffman, N3CVL       {allegra, bellcore, cadre, idis, psuvax1}!pitt!hoffman
Pitt Computer Science    hoffman%pitt@csnet-relay