repairfacts

WA4GEG FT-1000MP Series Notes

Back to Main Page

Back to Repair Facts Page

ATU / Antenna Tuning Unit & Outboard Tuner Cautions

How-to reduce the risk of damaging your transceiver when making use of the internal antenna tuner:

1) FT-1000MP series: Keep menu 4-3 (TUNING DRIVE) set for no more than 50 watts of power (75W for the 200 watt Mark-V.)

2) Always measure your antenna's SWR before activating the internal tuner, i.e. RF Power set for about 10~20 watts, CW mode, and PTT your mic. and read the SWR on the transceiver's meter. The tuner is not designed to tune non-resonate systems and an SWR close to or greater than 3:1 etc. Attempting to tune an out of range or otherwise non-tunable loads risks damage to T/R, ATU and expensive RF power amplifier components.

3) FT-1000MP, Mark-V and Field: If you don't normally use the internal antenna tuner, it is best to disable it by setting menu 8-8 to OFF. This will eliminate the risk of accidentally initializing the tuner by bumping the tuner's START button during otherwise normal operating activity.

4) Initializing the ATU into an open circuit (i.e. no antenna connected,) faulty and or intermittent load is a known cause for damaging the RF Power Amplifier and/or LPF Unit, especially for the 200 Watt Mark-V.

5) OUTBOARD TUNER WARNING: The 200 Watt FT-1000MP Mark-V is not bullet proof! Use extreme care when adjusting outboard antenna tuners. Most operators assume that it is safe to set the Mark-V for a low transmitter output power, and then adjust their outboard antenna tuner for low SWR - Wrong! Either relatively quickly if not over time, this incorrect technique is a known cause attributing to the destruction of the Mark-V's expensive 200 Watt RF Power MOSFET output transistors.

When adjusting external tuners the better method is to use an Impedance Bridge, such as one of the commonly available Antenna Analyzers, to find and log all adjustments for each band of interest. Thereafter the adjustment log is used as a guide to preset the tuner's controls to the proper range BEFORE transmitting a low power carrier to finalize the tuner's adjustments. Following this method allows the impedance presented by the TUNER to the Mark-V to be within operating specifications of the transceiver's protective circuitry.

ROLLER INDUCTOR TUNERS are the most troublesome of all outboard tuners. The maintenance factor aside, "hot tuning" roller inductors is a concern for even the older more rugged vacuum tube transmitters, and even more of a concern for solid state transmitters. The problem being that the continuity of the roller inductor's moving electrical parts seldom remains optimum, particularly while the roller is in motion. SWR spikes occurring while tuning roller inductors is a known cause for damaging solid state transmitters, to say the least.

FT-1000MP Mark-V (not Field)

WA4GEG's Receiver Antenna FUSE LAMP mod. (Tuner-Main update)

FT-1000MP Mark-V (not Field): The T/R switching circuitry is known to fault under certain conditions, most commonly when transmitting into high SWR, open circuit, faulty antenna system, and improper use of the ATU. The unfortunate end result is multiple component destruction on several circuit boards.

The addition of an antenna fuse lamp (pictured below) in the receiver's main antenna signal path will save $$$ in repair costs. This update modification is automatically applied to all Mark-V's serviced in my shop. The fuse lamp will also open and protect the receiver front end when dangerously high RF levels from a nearby transmitter enter the Mark-V via its main antenna input.

Menu Settings

FT-1000MP, Mark-V and Field:

In the course of servicing, and to properly align these transceivers, it is necessary to set certain user menus as follows. These settings also give the highest analog operating performance for the transceiver, including the best receiver SNR for all bands 160 through 12 meters. (For best 10 meter receiver *SNR, set menu 8-4 to tuned.)

4-4       TX Audio ESDP                                         OFF
5-0      (only for **Mark-V & Field)                    OFF (OFF = 2.4 KHz filters ON, as odd as it seems)
7-7        EDSP modulation and demodulation      OFF, OFF, OFF, and OFF
8-4      Front End RF Amp Selection                    FLAT
8-9      Carrier Offset                                        All ranges set to all zeros

*SNR = Signal to Noise Ratio. The lower the SNR, the better the weak signal reception, assuming low noise conditions etc.

**I commonly find menu 5-0 set to 8.2 - 455 in many Mark-V and Mark-V Field transceivers. This "mal-setting" defeats the internal 2.4 KHz crystal filter when the filter selection BANDWIDTH is set to the NOR position. The 2.4 KHz filter is available when the BANDWIDTH NAR-1 is selected however. Such a menu "mal-setting" makes it appear as if the transceiver has a narrow option filter installed at position NAR-1, which is normally reserved for the 2.0 KHz option filters (when in SSB mode.) And more importantly, performance suffers in that the receiver's IF circuitry is exposed to adjacent frequency interference. Such a menu setting is useless for serious SSB/CW work, and should be avoided - unless perhaps you have an after market narrow roofing filter installed (i.e. Inrad Roofing filter) and desire listening through the 4.5 KHz nominal bandwidth of the after-market "roofer."

FT-1000MP Mark-V, Linear Power Supply Replacements for the dual voltage FP-29:

For the 30-VDC requirement, most 28VDC linear supplies when turned up to 30 volts work well. One supplier for such a supply is Astron, i.e. the Astron LS-25A:

http://www.astroncorp.com/w28.shtml

For the 13.5 VDC requirement, use a regulated supply good for at least 3.5 amps. continuous duty.

Wiring:

The Mark-V DC power cord is then wired as follows to the substitute power supplies. WARNING, observe correct polarity and correct connections to prevent damage to equipment!

Connect to the 13.5 VDC power supply:

Small ORANGE wire to (+) Positive
Small GREEN to (-) Negative

Connect to the 28~30 VDC power supply:

Large RED wire to (+) Positive
Large BLACK wire to (-) Negative

Small white wire: no connection
Small gray wire: no connection

Note; The Mark-V will be fully functional on receive when powered from the 13.5 VDC supply.
Once the transceiver is up and receiving, activate the 28~30 VDC supply to enable the TX 200 watt amp.

FT-1000MP, Mark-V & Field notes

VFO A/B resetting to 7.000.00 at switch-on is a common symptom many MP series transceivers tend to develop over time as the units age. Sometimes this annoying but mostly harmless characteristic will remain over several power-on cycles and then straighten up on its own.

Unless the problem is related to a hard fault in the CNTL Unit board, cycling the back-up battery ON/OFF switch several times may correct it. Cycling the switch burnishes-in its silvered contacts restoring any lost continuity. Stubborn cases may require switch cleaning with contact cleaner, then de-Ox treatment.