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Re: [Amps] Alpha 87a No RS-232

To: Mark Bitterlich <>, "" <>
Subject: Re: [Amps] Alpha 87a No RS-232
From: Gerry Hull <>
Date: Thu, 5 Jul 2018 17:25:12 -0400
List-post: <>
Thanks, Mark.  This is not my first rodeo.  I use the RealTerm suite to
monitor, analyze and monitor RS232.
As I  said in an earlier post, I use Digiport Terminal servers (Rs-232 over
IP) to eliminate many of the PC isssues.

It’s too bad Alpha had not socketed these ICs from the start.  However, if
you measured the QSO-to-Repair ratio on the 87as, I think you would be
looking at 300,000 to 1 or more.  So not much to complain about!


Gerry W1VE

On Thu, Jul 5, 2018 at 5:17 PM Mark Bitterlich <> wrote:

> Hello Gerry.
> The MAX232 IC is infamous for this kind of problem.   They were used in
> some
> of the early Packet Radio TNC designs, and every one that was soldered in,
> I
> pulled out and installed a socket to ease future replacement.   The bottom
> line is that typically with Tx & Rx data, along with any CTS/RTS
> hand-shaking connected (with LONG wires to this chip), you have the perfect
> setup for any kind of lightening EMP to come in and wreak havoc.  Of course
> these TNC's were installed at remote commercial tower sites, so in the end,
> I purchased RS-232 surge protection devices and put one at both "ends" of
> the RS-232 cable, because as another writer mentioned, it also typically
> came in and took out the computers UART chip as well.  Back then 16450 and
> 16550 devices.
> Just as a note, any RS-232 kind of ham will tell you that having an RS-232
> monitor is close to essential in troubleshooting.  These things are
> available all over the place for $10 or less.  You want to look at the your
> Transmit and Receive data lines and check their status, as well as any odd
> hand-shaking indications that might be present.
> But for what it is worth, I'd start with the MAX232 itself, and after
> carefully unsoldering it, install a socket.  :-)
> Mark
> Wa3jpy
> -----Original Message-----
> From: Gerry Hull <>
> Sent: Monday, July 2, 2018 7:49 AM
> To:
> Subject: [Amps] Alpha 87a No RS-232
> Hello All,
> We have two Alpha 87as at K2LE.   They have been rock solid amps for
> decades.
> However, we operate remotely, and rely upon RS-232 using the great DF3CB
> software.
> We have the same failure mode in both amps.   The TX side of the serial
> port has failed.   We can command the amp on,
> But that is it.   We have verified multiple times and multiple ways that
> the cable and ports are working perfectly (short TX/RX Pins on the amp-side
> connector and ensure echo on a terminal program).
> I see very little about this subject in the archives.  Has anyone else
> experienced this?
> Does anybody know if the Max232 chip is soldered?   This is what I suspect,
> since the amplifier is fully functional otherwise.
> Is there some master reset we can try with a combo of front panel buttons?
> Your collective wisdom appreciated.
> 73, Gerry W1VE
> For Andy, K2LE and the team
> --
> Gerry Hull, W1VE  Hancock, NH USA
> Member: ARRL, YCCC, YCCCN, CW Ops
> ph: 1-617-CW-SPARK (find me)
> _______________________________________________
> Amps mailing list
> --
Gerry Hull, W1VE  Hancock, NH USA
Member: ARRL, YCCC, YCCCN, CW Ops ph: 1-617-CW-SPARK (find me)
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