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Frequently Asked Questions
Good news: We have created a "universal" serial interface to facilitate a myriad of radio-to-AT-AUTO configurations and which is available for purchase. Please follow the link under Products, then AT-AUTO Tuner Cables. The "universal" interface eliminates the need for different radio-specific cables and only uses "normal" 9-pin serial cables. The interface has three switches that permit quick selection of mode as well as radio-specific settings. This is probably the best option for your situation and it less expensive than buying multiple sets of cables, etc.
We do not offer a Linux version of the bootloader program, but it works perfectly in Linux by using WINE. BTW, we are primarily Linux here as well and we use the bootloader (via WINE) in Linux almost exclusively to upload and test new firmware versions.
If you need to use a different COM port (other than 1-4), you may edit the initialization file used by the bootloader program. Locate the tinybld.ini file and open it with a text editor. At the top of this file you will find a line that reads COMport=COM1 (for example). Change COM1 to COM9 (or whatever specific COM port you plan to use). Save the tinybld.ini file, then restart the bootloader program, and the selected COM port should be displayed, etc.
Thanks for asking. The "Multiple Input Rig Switching" feature was implemented in Firmware version 2.14, and has been available since approximately August, 2011.
The roller inductor has a contact wheel which rides back and forth along the length of the roller inductor. The contact surface between the contact wheel and the contact wheel shaft is where the sound is emanating from. It needs to be lubricated.

Visit your friendly neighborhood hardware store and purchase a very small tube of white lithium grease and some graphite powder. Take a small portion of the white lithium grease (about the size of tip of your index finger) and start mixing in graphite powder until the mixture is dark black, and is the consistency of thick yogurt.

Remove the top-cover of the AT-AUTO. Look at the roller inductor and you will see the wheel shaft -- it is parallel with the axis of the roller inductor. Remove the existing lubricant from the wheel shaft by wiping it with a paper towel. The apply small amounts of the lubricant ONLY to the wheel shaft. A Q-tip works well for this. Only apply a very minor amount. A little bit of this lubricant goes a long way. More is not always better.

Turn on the AT-AUTO, enter Manual Mode, and motor the inductor back and forth from one end of travel to the other. Wipe off any excess lubricant, being extremely careful NOT to get any of this mixture onto the coil.
Since inception of this product, others have decided to support it as well. Software support has been included in DDUtil, Ham Radio Integrator, and is also supported by the Remoteshack hardware system.
First -- Thank-You for being patient. I had in good-faith believed that it would have been ready long before now and had given estimated dates that I was subsequently unable to live up to. I don't want to keep stringing folks along. I'll explain the on-going circumstances and let you make your own conclusions.

The electronic and mechanical design work was completed months ago and component sourcing for the meters, motors, and the vacuum capacitors, etc., had been completed in August, 2011. The delays center around the variable inductor.

A major problem associated with high-power tuners that utilize "roller" inductors is their reduced Q, significant inductor power dissipation, and the roller inductor's in-band resonances. In order to avoid these problems the AT-AUTO II uses a sophisticated variable inductor (NOT a roller inductor), which while electrically superior, is more mechanically complex than a roller inductor.

This inductor (.5-35uH) works very well. However, its production delay is due to problems finding a U.S. manufacturer to produce some of the variable inductor's sub-components. I have found several production facilities but their pricing has not been acceptable.

This has delayed both the sourcing of the inductor sub-components and subsequently the Bill of Materials. Without an approximate Bill of Materials, I can't definitively determine overall price.

The AT-AUTO II uses the variable inductor (discussed above) in a "T" configuration comprised of two 15-750pF, 10kV vacuum capacitors. The "tuning unit" has 8 coaxial outputs and is designed to be remotely located, and communicates via fiber-optic cable with a "control head" located in the hamshack. The tuning unit may be located practically any distance away, the only limitation being the RF feedline between the tuning unit and the radio transceiver. The fiber-optic cable is able to work over several km.

The 8 coaxial outputs can be used any combination, such as feeding multiple elements simultaneously (think antenna array).

The "ballpark" price of the AT-AUTO II is $3,200 - $3,600. Soon I will be adding a section on the website specifically for the AT-AUTO II.
The modification kit, dubbed "TL-922 Revival", is available for purchase. Please click here for the TL-922 Revival Kit page. The kit includes everything for the electronic bias, soft-keying, QSK (including the vacuum relay), etc. It does not include the parasitic modification components.
Sorry, no. I stopped working on these amps in 2008. I do not foresee having the time to work on these amps, but thanks for asking.
We have obtained all rights to the AT-AUTO and will begin manufacturing a revised version with new hardware features. Kessler Engineering will continue to update the firmware and provide support for all versions of the AT-AUTO . After 30 July, 2010 the previous manufacturer was required to cease production of the AT-AUTO.
Yes. As part of the on-going AT-AUTO product development and improvement, firmware updates are still being developed and are made available to any owner of any AT-AUTO. The firmware is available via a windows program which you will need to download and install on your computer. This bootloader provides the option of selecting several firmware versions which then download and can be install on your AT-AUTO.
Yes. You have the option with the bootloader to pick from a selection of available firmware versions. However, we generally have 2-3 different firmware versions available, but we do not provide access to every firmware version.
You have two options. We would prefer that you purchase the accompanying CX-AUTO which provides eight coaxial outputs. However, if you prefer to simply add a second coaxial output and don't need the balanced output, we recommend the following procedure:
  1. Unsolder the balun lead at the antenna relay.
  2. Remove one of the balanced output connector "Bolts" and associated nylon insulating hardware.
  3. Insert an SO-239 connector in the vacated balanced output connector.
  4. Solder a #14 wire from the center-pin of the SO-239 connector to the relay contact which previously went to the balun.
If you follow these steps, this modification can readily be "undone" and no added holes, etc. will be necessary. The firmware will associate the "new" coaxial output with the "Balanced" memory settings, etc., and will be selected whenever "balanced" or "bal" is shown in the AT-AUTO display.
Yes. The CX-AUTO employs a microprocessor which normally communicates with the AT-AUTO using the CI-V command protocol developed by Icom. The CX-AUTO is controlled by sending it serial data command strings (described in the CX-AUTO owners' manual), and does not require an AT-AUTO so long as your remote station is able to communicate with devices on a CI-V style data bus.
Yes. We offer repair for these older units but you need an authorization number (RMA) prior to sending an item to us for repair. Please submit a repair request (visit the Contact page) and we will communicate with you directly.
We warrant our products for a period of one year from the date of purchase and repair work is warranted for 90-days.
Please contact us directly with your warranty request via our Contact page and we will provide an RMA number as well as shipping information.
We have several other products that are in various stages of development. However, we prefer not to divulge particular details until they have completed beta testing and are much closer to being production-ready. When we are at a point where we can offer them for sale and immediate shipment, we will showcase them on our website.
Yes! The "AT-AUTO II" prototype hardware was on display at the 2014 Dayton Hamvention® and was even featured in a video by the fine folks at "Ham Radio Now" and can be viewed at the following URL: http://arvideonews.com/hrn/HRN_Episode_0155.html

The AT-AUTO II is a very high-power, remote, automatic antenna tuner (coupler) that places the tuning network (T-Match configuration with two 15-750pF, 10kV vacuum variable capacitors and a Collins-style "dual-drum" variable inductor) and communicates via fiber optic cable with a small-footprint control head located in the shack. The tuning network features eight coaxial outputs and has its own built-in, universal voltage, AC power supply.

The firmware is undergoing some updates and the tuners are expected to be released to the beta testers VERY soon!
Since original inception of the balanced switch, there has been almost no interest in this device, so it will remain a very low priority.

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Kessler Engineering, LLC
Box 2
Davis-Linden Bldg.
402 Linden Ave.
Dayton, OH 45403

Tel: 937.458.3173

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