TuneMatic tech notes

TuneMatic technical notes from actual emails received and responded to (updated 05/27/2020)

Why not use tune button on rig?
Although many rigs contain a ‘tune’ button, they are typically designed to interface with a manufacturers recommend tuner. Most of the time, there may be sophisticated communications protocols between the rig and the tuner. Rather than try to manipulate the protocols, which on occasion, may not be reliable, TuneMatic contains a small remote button panel, which contains all the functions necessary to operate TuneMatic with your rig.

Secondly, by using our own controls, it enables TuneMatic to operate on both current and legacy rigs, as many legacy rigs are not equipped with a tune function.

Yaesu FT857/897/991/891 changing the ALC settings to work with TuneMatic :
Those settings do not matter with TuneMatic operation. TuneMatic interfaces with your radio through the accessory port keyline. When this port sees a ground, it places the rig into 100w CW tune mode. At the same time, an ALC generator inside the interface box sends a negative voltage (depending on how you adjust the pot) to reduce the power to a safe tune level (10-15 watts). The DIN plug you inserted into the rig from the interface provides the on/off switching of the microprocessor in the TuneMatic and remote backlight, as well as the power to the ALC circut in the interface box.


Encountering bad tunes:

When TuneMatic keys the rig, it measures the frequency and swr/power. There is an internal frequency counter that actually measures the rig transmit frequency. At the same time, it is measuring the pulse count and antenna current, in case it goes past the soft limits and stalls out.

The newest software does not require the user to press the TUNE button a second time after it moves to the memory frequency. The original intent was to allow the user to either allow the second portion of auto-tune, or just allow it to timeout. This version does this automatically, but you can bypass the auto feature, by holding the INIT button(2 small circled arrows) on power up. It resets back to full auto on next power up.With the newer software, it is a feature option.

The EEEEE message indicates that it assumed the frequency was already stored, when it keyed the second time, it didn’t like the SWR reading, and it was warning you that the SWR was not acceptable to TuneMatic limit.

Keep in mind the auto SWR tune feature can depend on many outside parameters. My recommendation is to manually store favorite frequencies, and you won’t have any odd issues like you experienced.

RODA antenna :
TuneMatic utilizes pulse counting and current sensing as well as frequency and SWR parameters from the antenna.

From what I read on the site, the RODA antenna utilizes a ‘Turns Counter’ circuit, according to their documentation, as well as a thermal current limiting device in case of antenna overload. What I do not know is how quickly this current limiting device operates, as TuneMatic also contains a current limiting feature. Hopefully TuneMatic will sense the current first, but I would recommend contacting the manufacturer to determine when their limiting occurs.

Does the Kenwood TS-480SAT work together with your tuner (interface)?
Yes, it it directly interfaces. The connections are to the antenna tuner port (for power to wake up the micro in TuneMatic), and the serial RS-232 connection (to communicate with the rig). The interface box sends specific TXTUNE commands to the rig to key it in a safe 10w power level.

Can I extend the interface control cable from the TuneMatic to the interface unit?

Yes, the cable from TuneMatic to the rig interface box is a standard PC-style power connector, typically found in most Personal Computer power supplies. The cables from the box to the rig are approximately 0.5 meter, but I can customize one for you if you need.

Antenna motor connection on non-TarHeel antennas:

Typically TarHeel supplies an extension cable from their antenna to a male plug, which mates with TuneMatic 4 pin female square connector. If you do not use a TarHeel antenna, we can supply a pigtail. You must specify this need when ordering. Other manufacturers typically supply their own cable from their antenna, so the pigtail would connect to the manufacturers antenna cable. It allows quick connect and disconnect to the TuneMatic motor cable.

If you want to make your own pigtail cable, the mate and pins for the 4 pin square connector for the motor is:
Connector, male, 4 pin 0.062 series Molex 03-06-2044
Pins, male, 0.062 series Molex 02-06-2103

Available from www.mouser.com or similar companies.

Heed the pinout wiring (1 & 2 is motor, 3 & 4 is pulse sensor) Pins 1 & 2 can be easily identified as the pins between the notch in the connector.

Power rating:
TuneMatic will operate up to 200 watts. If you plan to use additional power with an external amplifer, you would connect the amplifier AFTER the TuneMatic unit. We offer a relay option, which causes the keyline from the rig to the amp to open during TuneMatic operations.

You said ” This interface supplies RS-232 commands to the user” Does this mean the Tunematic sends commands to the radio?
No, the TuneMatic sends commands to an external monitor, RS232 device, or something that can accept RS232 data at 57600 baud. The commands are in lieu of the Morse messages, for the purpose of an external LCD display (future product). The RS232 was already incorporated into the software, so it is already available.

Does the radio send commands to the Tuner such as frequency to tune to?
No, the frequency is read off the antenna/rig port loopthru.


I have designed and built a multiband ground plane 1/4 wave vertical that adjusts the length of the radiating element with a motor, similar in concept to the StepIR vertical antennas.
Do you see any potential problems using your Tunematic controller on my antenna?

As long as you have a means to measure motor rotation (like most screwdriver antennas), it will work. TuneMatic is dependent upon the pulsecount of the antenna, so that it can recall and return to a stored pulsecount.

DC power:
The black wire is the ground(negative power lead) . I would recommend connecting the red and black leads in parallel with your rig connection power. The ground screw on the chassis is optional. Take note that the black wire also connects to chassis, but you won’t hurt anything connecting a separate ground (to your vehicle chassis for example) as well. This is a standard 6-32 thread.

First start on setup:
Set your DIP switches. then make sure the antenna moves up and down with no current limit conditions (prior to initialization). If it does not stop prior to reaching either end, then it should be a good starting point.

What happens and how it works in general:
As you probably know, TuneMatic adjusts the resonant frequency of the antenna, by monitoring the pulse count (a sensor in the antenna), motor stall (where current rises at end of travel), RF frequency, and the VSWR of the RF passing through the connection between TuneMatic and the antenna.

TuneMatic uses the accuracy of the pulses from the antenna to remember where to return to when recalling memories. The process begins after you “initialize” the antenna, whereas the motor moves to one direction (upwards=lower frequency) until it reaches the current limit point of the antenna, then moves down, counting pulses until it reaches the bottom limit. From there, it ‘parks’ the antenna at the lower soft limit (a point a few pulse counts away from the current limit); both ends of the antenna have the soft limits set once the max pulsecount is known.

When setting up the antenna, the user is instructed to set a reference point in each band (best tune). These points are stored, so that when the user wants to recall and return, those points are the starting points to begin at for each band. So when the user presses the TUNE button on the TuneMatic remote, it keys the rig for a 1/2 second or so, measures the transmit frequency, and looks up in memory where the closest frequency is to the transmit frequency, and moves the antenna to that reference point. It then stops, and keys the rig again, and either stays where its at (if the VSWR is <=1.5), or begins to tune away from the reference frequency, in the correct direction. Then it looks for an SWR ‘null’, passes through it, then returns back to the null. If the null is <=1.5, it stores it. If >1.5 but <2:1, it stops (but does NOT store the antenna position) at the null with the appropriate message. As more frequencies are stored, less time is spent requiring nulling and tuning. Eventually all frequencies can be stored and recalled with no additional tuning. First step autotune result:
TuneMatic has the ability to send a particular Morse code message in the first step in the tuning process. If it finds a match to the transmit frequency compared to the memory frequency, it sends an “AS” (already stored) message, indicating that the transmit frequency matches the found memory frequency, so that the operator can be made aware that the transmit frequency tune was a match to the memory window found.

Setting rig power with interface module:
Keep in mind, in the tuning process, the rig is set to approx. 10 watts when tuning, you don’t have to worry about setting the power when the unit tunes. Unless you have a legacy rig that requires tuning in AM mode, you don’t have to worry about setting the power on your rig for the tuning process.

Yaesu interface settings:
TuneMatic will operate from approx 5-35 watts. When you adjust the power setting with the ALC pot on the interface, adjust between 10-20 watts output. The exact power setting is not critical, but TuneMatic works best between 8-20 watts. More power is not good for the rig and antenna when tuning, and too little (under 5 watts) will be outside the tuning sensitivity of TuneMatic.

Motor connector interface mating connector
TuneMatic stores pulsecounts into memory ‘windows’ based on the resonant point of any given frequency. The resonant point is based on antenna whip length, physical position of antenna, and optimum SWR. When you store memories in TuneMatic, it is based on the same whip and antenna. If you change either one of these, the tuning points stored in memory (based on the pulsecount) will be completely different.

The timing of the initialization depends on the power supply voltage and length of motorized antenna, typically 90 seconds for most antennas.

When my Tarheel is attached to my car, often when I park I take off the standard mobile whip and place a much longer MFJ telescopic whip on it. Obviously this changes the resonance point, but by doing this, would it require your unit to reinitialize. Does “reinitialize” mean it has to take the screwdriver to one limit and then all the way back to the other limit before starting to tune? If so, I’m guessing that would take about 5 minutes with my antenna?

When you initialize, or re-initialize, TuneMatic is moving the antenna to the top current limit point (highest direction of travel, lowest frequency), it travels back in the opposite direction, counting pulses, until it reaches the bottom current limit point. Once it gets there, it then sets the ‘soft’ limits, and now knows how many pulse counts exists in the antenna, and which direction to start out at.

If you change antennas, re-initializing will not change the memory locations, because they were memorized based on the antenna they were programmed with. If you change out the antenna, All your memories will be out of alignment with the new antenna each time. Uness you have an EXACT replacement antenna, your memories may not match with the new antenna, and you will have to factory reset the TuneMatic.

HOWEVER, if you were using a different whip on a specific band, you could store the bands you operate whip “A”, then remove it, and store the bands you operate on whip “B”. The memories wouldn’t care which antenna was used, but you would have to remember which bands used which antennas. Otherwise you would get tuning errors that TuneMatic would not be able to easily correct. If the changes were slight, TuneMatic would automatically attempt to correct them, but large changes it would not.

How does the new version 5.x firmware differ from the older versions?

The biggest change is how it tunes the lowest SWR. With the current software, it looks for a dip, and memorizes the pulse count as it finds it, then returns the antenna back to the pulsecount that had the lowest dip. With the newer software, it works the same, except it returns back to the lowest SWR dip point instead of the pulsecount value, which results in more effective tunes, as the pulsecount is not as finite as the actual DIP.

The second change is during re-tunes (on existing memories). It will return back to the stored memory, but when it checks it, if it is unsatisfactory (>1.5), it will try to re-correct by moving up a few pulsecounts, then attempts to re-tune for a new dip. When it finds the new dip, it stores the new position. If for some reason it can’t find it, it then sends out the ‘e-e-e-e-e’ message, and parks the antenna. This allows the user to try the tune again, which automatically re-calibrates the pulse count when it parks. If it can’t find it on the second tune, then something is seriously wrong. It will repeat the process each time again.

This significantly helps the little tarheel antenna tuning performance. We only charge the customers a small handling fee to process the paperwork, etc. and request the old chip back. Changing out the chip will not affect memories or settings, so it is a seamless swap out.

When I initialize the antenna, it moves about 1/8 of the way up, then stops with a “PE” error. What is wrong?

The PE error indicates there are no pulses being detected. To check, manually move the antenna and look for the sun symbol flashing during movement. If it is not flashing, then you don’t have pulses. You can self-troubleshoot by unplugging the motor connector cable, and shorting the 2 leads OPPOSITE the notch with a paper clip (pins 3 & 4). The sun LED on the remote should remain on. If it does, then re-connect the cable, and check at the antenna for the same result. As long as there is a short on the 2 pins 3 & 4 of the connector, the LED should remain ON. If the LED never lights up, there may be either an issue with the TuneMatic unit, or the remote cabling.
The latest firmware (5.42) has a buit in troubleshooting feature specifically for checking the pulse sensor operation with a continuous ‘beep’ when the sensor leads are shorted together.

When using the Scorpion 680 Antenna, I get the “PE” error, and have to re-initialize the antenna. What is causing this?

The Scorpion antennas use an 18v motor, and typically do not have enough voltage when TuneMatic is moving at the slower speeds. This is further enhanced when the vehicle motor is not running. There is an internal adjustment to speed up the slower motion on the antenna, and the v 5.42 firmware (as of 11/20/17) has additional compensation on the speed adjustemt to resolve this matter. Contact the factory for a Firmware update.

Whenever I intialize or move tne antenna,in stops with a “PE” error. What is wrong?

TuneMatic is not sensing pulses. To check this, disconnect the motor connector (the square connector with the notch). Position the female connector on the TuneMatic so that the notch faces upward. The two connections on either side of the notch are the motor leads, and the botom two are the sensor leads. With the power on to the TuneMAtic, short the two bottom ensor leads. Observe the sun LED on the remote, and it should remain on. If it does, you will need to repeat this step at the antenna for the same result. If the LED does illuminate, then there is an issue with the cabling or connections. If the LED does NOT illuminate, contact the factory for further troubleshooting assistance.

Predator mobile antenna, made by W9JMX

Here is my concern: when the Predator reaches the end of the coil, it doesn’t really stop. What happens, is that the Lexan cover starts rotating around the body of the mast. And during that time, it’s still throwing pulses out to the controller, and it will either count up more, or go negative after reaching zero.  It obviously doesn’t have any limit switches inside, but it has the reed switch to count pulses.

TuneMatic controllers rely on the stalling of the motor when it reaches end of travel. When this happens, the motor current rises, and TuneMatic senses the current rise (internally programmable) as end of travel. During the setup, the antenna enters an ‘initialization’ phase, where it travels to one direction, looks for the current rise, then starts counting pulses as it travels back, until the other limit is reached (by the current rise). Once it completes this task, it now knows:
1) The total number of counts from end to end,
2) Soft limits (a few counts from the current rise points),
3) The operating range of the antenna based on 1&2.

Then the antenna can then operate in the programmed range.  All TuneMatic products have a park feature, which also re-zeros the count.

Since your antenna does not physically stop, you would need a means to prevent rotation once it reaches the end. The TarHeel antennas contain a rib alongside the outside of the antenna housing, and a notch in the antenna shroud. This prevents the antenna from free-spinning, and allows it to fully stop when it reaches each end. Limit switches wouldn’t work, as it would never reach the current rise point, plus, if you disconnect the motor voltage while motor is moving, TuneMatic will detect this as a pulse error.

Using the TuneMatic with the Scorpion SA680 in a fixed (base) location:

  1. When using the Tunematic with a Scorpion 680 antenna, the slow speed voltage pot MUST be turned up almost fully clockwise.  That will provide enough voltage to drive the motor correctly at slow speed.
  2. Bumping the supply voltage up from 13.8 to about 15 volts is also helpful.  This will kick the slow speed voltage up to about 10v.
  3. The higher slow speed voltage may result in some slow-speed operations moving a little too fast for the Tunematic.  If this happens, the pot can be lowered just slightly to see if that helps, but do so carefully so as not to go too low.  I would suggest lowering it no more than about a half a volt at a time – the voltage can be measured across the motor drive FETs while pressing the up or down button in slow mode.

ATAS antenna use

TuneMatic products operate with a feedback sensor, in the form of a reed switch and rotating magnet for accurate tuning and memorization. Since the ATAS antenna does not contain this type of sensor, it will not operate with the TuneMatic. In addition, the ATAS antenna uses a stepped voltage on the coax line to change direction, whereas the TuneMatic uses a floating set of leads on a bi-directional motor, which reverses by changing polarity on the motor leads. Since the ATAS antenna does not work with bi-directional power, it will not work with the TuneMatic.

The ATAS antenna is specifically designed to work with the Yaesu rigs only, and are not designed to work with any other radio. TuneMatic will operate with a wide variety of radios, but only with screwdriver antennas with the proper connections to the motor.