Alpha 87A SmartSDR settings & DDUtil setup

Randy Hollingsworth · January 2016

Are the TX setup settings for the Alpha 87A amp the same as the ones for the Alpha 9500 that I have seen posted here? Also, any guidance on setting up DDUtil for use with the 85A would be appreciated. I already use DDUtil with my 6500, but not sure what needs to be set up to have DDUtil handle band switching on the 87A.

I have also seen some posts that suggest the use of a buffer box between an amp and any of the Flex units. Having used the Alpha 87A with an ICOM 756PROII for several years, I doubt I need one, but thought I better check in case there is a compelling case to use one with the FLEX units. Thanks!

Charles - K5UA · January 2016

Hi Randy, One of the best things about the Alpha 87A is that it does not need band/freq data from the Flex or any other transceiver. It has an internal freq counter thats sets the 87A for the correct band and freq segment. Change bands on thr transceiver, select the correct antenna, and start transmitting. The 87A will do the rest. T

Walt - KZ1F · January 2016

Hey Charles, I have a question about that. The KPA-500 does the same thing as does, I am sure, the Alpha 9500. So this question applies to all of the linears that do that. As it involves relay switching therefore some > 0 amount of time, does that amount of time when the linear is off band, hurt either the main radio or the linear itself and/or does it not bring up power until it resolves the freq/band of the exciter, thereby chopping off some part of the initial transmission, especially for CW?

Charles - K5UA · January 2016

That is true Walt. There is a momentary switching time when the exciter power routed thru to the antenna as the stepper motors adjust the tune and load components to their proper band segment. When they are adjusted the exciter power is applied to the amp and the amp is connected to the antenna. I would guess it takes about a half second, a bit longer if going from 160m to 10m. But how convenient, no serial port cables, no usb cables, no virtual CAT ports, no port sharing software......make sure the right antenna is selected and start talking. If that half second is a deal breaker, be prepared to spend a lot of time playing with CAT commands and port sharing software. I know this from experience trying to get my OM2500A to work with the Flex.

EA4GLI · January 2016

My SPE has the frequency sensing capability, but I personally don't like that mode of operation that always requires me to TX to have the amp follow.
Sending band data to the amp to change on band changes only for RX is very convenient.

Randy Hollingsworth · January 2016

Charles, thanks for the input. I currently use the internal Alpha 87A capability for band switching, just wondered if there was a reason for the folks that shifted to using DDUtil. Are you in agreement with using the other Alpha 9500 SmartSDR setting info that was published for the 87A, i.e. TX1 enabled, 0 msec delay, TX delay = 20 msec, tune power = 40 watts?

W1IMD · January 2016

I have used DDUtil to band steer my 87A for years. I find it easier to have the amp already on frequency than to hit it with RF and have it try to catch up. Setup via DDUtill is a snap, the only funkiness is the DB 25 connector on the back of the amp. Pin 21 gets removed from the cable IIRC. Do take the time to do this, you'll be glad you did.

Charles - K5UA · January 2016

If you don't mind listening to the stepper motors reposition everytime you change bands just to listen for activity, and if you don't mind setting up ddutil and the appropriate cabling to achieve communication between the amp and the transceiver, then ddutil will do the job. However, for a true automatic amp like the 87A or the 9500, a simple momentary depression of the PPT foot switch or a single dit on the keyer, once you want to committ to a band change, will reposition the stepper motors before you make the first transmission on the new band. After the grief I personally experienced getting my 6500 to communicate reliably with my OM2500A amp, I feel that any amp that requires frequency data from the transceiver to change bands should not be called an automatic amplifier, they should be called semi-automatic. This is, of course, only my personal opinion.

EA4GLI · January 2016

I am a lucky one, my amplifier is fully automatic, as I stated before, it has the frequency sensing feature. I just don't use it. With the SPE Expert all I needed is one single serial to usb cable from the amp to the pc, which allows me remote control of the amp are well as band changes. That is it, no more cables. I have different antennas for different bands so it is nice to have the amp select the G5RV for 80m without having to send any watts to the wrong antenna for a second avoiding undue stress on radio and amp. Additionally, by having the amp do band and antenna changes based on what I or DDutil, ( and it seems very soon cat on ver 1.6 of SmartSDR) I can have several radios work with the same antenna/amp without having to create any other cables from the radios to the amp. CAT sends band info to the PC, DDutil transforms that into a band change at the amp. Very easy, takes me 2 minutes to setup. I can see some signal on the panadapter, put the slice there and i don't have to bother anyone with a whistle or a tone to get everything ready. I don't need to find an empty frec to get the amp ready. I can have someone, like i did yesterday, remotely connect to the 6700,and they can go to whatever band they desire and have the amp and antennas follow automatically without TXing. I find that very automatic.

keith hertzog · November 2022

I would like to be able to use DDUTIL to control a serial port on my 6400. In turn send commands to my alpha 87a. Not for band switching at all. I would be able to power up the amp, operate standby, read the feedback on output power. ETC. . DDUTIL does fine from the serial port on my local pc. I would like to control from the 6400. Any Ideas ?

73 keith

KD0RC · November 2022

Hi Keith, I don't think what you are asking for is possible.

I control my KPA-500 / KAT-500 combo from DDutil using an old laptop when I am remote. When I am home, DDUtil runs on the same computer as SmartSDR.

Are you trying to control the Alpha when you are operating remotely?

keith hertzog · November 2022

thanks Len, Just saw message. Yes remote. I would like to be able to run alpha remote from a remote PC. DDUTIL is fine as stated on the local PC. Also Alpha Remote operates well. I would like to run alpha remote from a remote computer by controlling the serial port on my main PC which is always on anyway. doesn't need to tie into smartSDR. I don't want a complete remote PC software Just a TCP from remote. I seems like there would be a utility somewhere that would capture the local serial commands (from alpha remote ) to the actual serial port on the host PC at the shack. Any ideas?

Thanks In advance

73 Keith N3SVB

Alpha 87A SmartSDR settings & DDUtil setup

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