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Reviews For: Am-Com Automatic Screwdriver Antenna Controller

Category: Antennas: HF Mobile & Accessories

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Review Summary For : Am-Com Automatic Screwdriver Antenna Controller
Reviews: 21MSRP: 210.00
Description:
An Automatic Controller for Screwdriver Antennas
Product is in production
More Info: http://www.amcominc.com
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
00213.7
N6FM Rating: 2001-11-11
Automatically Adjusts Screwdriver Antennas Based on SWR Time Owned: 0 to 3 months.
I bought the contoller at the introductory price of $189.95. This special price offer ends on November 30, 2001. The controller is made to directly plug into the IC 706 family of radios and the Alinco DX70, but can be used with any radio capable of providing a carrier for tuning purposes. The control head contains up/down buttons and a speaker which provides aural feedback of direction, mode, successful completion of a function, and error conditions. The controller automatically adjusts the screwdriver until the desired level of SWR is obtained. It is not an antenna tuner, but actually controls the movement of the antenna. You can set the desired target SWR as part of the setup process in case you desire a different SWR level to be met than the default of 1.5 to 1.

After installing the controller, and while using a Don Johnson Screwdriver and IC706MKIIG, I found that it did tune but not quite as I had hoped. It seemed erratic. Following the manual's instructions, I added resistance to the motor lead, which slowed down the antenna and mitigated the overshoot I was also experiencing. Apparently this also cured the cause of the erratic operation which was perhaps caused by motor whine or some other anomaly. One setup test that it failed was the end-of-travel test where the system measures the difference in the motor current when the motor reaches end of travel and stalls. Apparently my screwdriver's motor doesn't exhibit a great change of current when it reaches the end of travel. Since the system tunes based on SWR, I decided it wasn't important but will be asking Am-Com about it.

The controller now tunes correctly, although the length of time the antenna requires to reach 80 meters causes a timeout to occur. An additional activation or two on the radio's tune button is sometimes required.I will be experimenting with resistor values in an attempt to obtain the fastest speed while maintaining reliability. And it may also start in the wrong direction with the appropriate beep, but a press of the button for the correct direction immediately reverses travel. The manual covers both of these situations.

For my purposes, this product provides welcome relief from having to watch a field-strength meter, key the mike to obtain carrier, and at the same time manipulating the switch to move the antenna to the correct position for operating while driving in traffic or on winding mountain roads. Since I have not owned a screwdriver for long, I cannot comment on the other devices designed to aid in adjusting a screwdriver antenna. My experiences have been with Hamsticks, Hustlers, Band-spanners and other Webster products, etc. The Automatic Screwdriver Controller works as advertised, and I am glad I purchased it.