[ICOM] Amp Keying Question Again

[paul at w8aef.com]

With my PROII the RF envelope is delayed by 8ms from the keying line.  I do 
have a problem with QSK because the ACC(2) keying line goes unkeyed before 
the end of the RF envelope.

When I run my Alpha amplifier during QSK the PROII transmitter sees an open 
circuit when the reed relay on the input to the Alpha unkeys and the alc in 
the PROII partially shuts the transmitter down for subscequent elements.

The work around is I use the PROII's relay output, which stays closed until 
the element is completed.

de Paul, W8AEF


----- Original Message ----- 
From: "David J. Ring, Jr." <n1ea at arrl.net>
To: "ICOM Reflector" <icom at mailman.qth.net>
Sent: Wednesday, June 22, 2005 6:58 AM
Subject: Re: [ICOM] Amp Keying Question Again


> How about sequencing, Adam?  When keying from ACC(2) pin 3 of the ICOM
> exciter, does that pin switch at xx milliseconds before r.f. is generated?
>
> In otherwords, can I hook up my amplifier relay to ACC(2) pin 3 have the
> relay be energized and then the ICOM exciter generates r.f.?
>
> I've seen some elegant solutions to hot switching - including a bucket
> brigade delay which divided the voice signal (which activated the VOX) 
> into
> two components - the first activated the amplifier relay.  The second was
> time delayed by 20 ms by the bucket brigade digital delay and then fed to
> the microphone input of the exciter.
>
> Thus no hot switching - and no missed first sylables caused by VOX 
> clipping
> because the VOX was turned on by the "real-time" speech, but that speech 
> was
> delayed digitally and fed to the exciter - so it never got chopped off. 
> No
> need to say "ahhhhh".
>
> The problem with some of the digital modes, and CW QSK is that the r.f. is
> hot switched.  I've seen amplifiers that show this damage - it often 
> causes
> the relays to arc over and burn up - especially with high power commercial
> installations.
>
> I haven't investigated this with the ICOM radios, I wonder if anyone has.
>
> 73
>
> David N1EA
>
> ----- Original Message ----- 
> From: "Adam Farson" <farson at shaw.ca>
> To: "ICOM Reflector" <icom at mailman.qth.net>
> Sent: Tuesday, June 21, 2005 11:13 PM
> Subject: RE: [ICOM] Amp Keying Question Again
>
>
> Hi Dave,
>
> Actually, when keying an amplifier from ACC(2) Pin 3 of an Icom exciter,
> there is no need to disable the reed relay. For example, the Icom IC-PW1 
> is
> keyed from ACC(2), and the exciter's reed relay has no function.
>
> Cheers for now, 73,
> Adam VA7OJ/AB4OJ
>
> -----Original Message-----
> From: icom-bounces at mailman.qth.net
> [mailto:icom-bounces at mailman.qth.net]On Behalf Of David J. Ring, Jr.
> Sent: Tuesday, June 21, 2005 15:33
> To: ICOM Reflector
> Subject: Re: [ICOM] Amp Keying Question Again
>
>
> There are some ideas for QSK and speeding up transceiver switching (namely
> eliminating the relays) for some transceivers.
>
> http://www.somis.org/QSK922.html
>
> I am not the author of the page, but the author is held in high regard by
> many.
>
> 73
>
> David N1EA
>
> ----- Original Message -----
> From: "Adam Farson" <farson at shaw.ca>
> To: "'ICOM Reflector'" <icom at mailman.qth.net>
> Sent: Monday, June 20, 2005 1:56 PM
> Subject: RE: [ICOM] Amp Keying Question Again
>
>
> Hi Joe,
>
> The amplifier keying relay in an Icom transceiver cannot be disabled, but
> you may be able to connect ACC(2) Pin 3 (SEND) to the AmpKeyer input. The
> SEND line is bi-directional; it goes low on transmit, and grounding it
> externally keys the transceiver. The relay will still operate, but keying
> from the SEND line eliminates the relay's 1 mS latency.
>
> Cheers for now, 73,
> Adam VA7OJ/AB4OJ
>
>
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
>
>
> Scanned by WinProxy
> http://www.Ositis.com/
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
>
>
> -- 
> No virus found in this incoming message.
> Checked by AVG Anti-Virus.
> Version: 7.0.323 / Virus Database: 267.7.8/22 - Release Date: 6/17/2005
>
> ----
> Your Moderator: Dick Flanagan K7VC, icom-owner at mailman.qth.net
> Icom Users Net: Sundays, 1700Z, 14.316 MHz
> Icom FAQ: http://www.qsl.net/icom/
>
>