WA4GEG Notes; FT-1000MP Mark-V series


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                          CLASS-A Caution, 200 Watt FT-1000MP Mark-V                                


Many an operator has fried the final stage output RF power MOSFET (transistors) by using the Mark-V's Class-A mode as a convenient way to limit TX-PO to 70 watts for key down antenna tuning and etc. Long duration Class-A operation (key down time) results in very serious overheating of the final stage transistors, guaranteeing premature breakdown failures in very short order. I.e. key down Class-A, with no RF power output, biases the final stage MOSFETs' to 300 watts DC input power, which translates to 300 watts of continuous heating, a level of heating that can not be conducted from the transistor's die to the aluminum heat sink fast enough to prevent transistor breakdown. This is not a cooling fan issue, rather the ICAS heat sink design, which does not have an integrated copper heat spreader. Those who get by running Class-A, are those who operate SSB VOX Break-in with very short VOX delay (hold) times. However, the astute operator and those with very thin wallets, would do well in completely avoiding the use of Class-A for any purpose.

To get the most service life out of the Mark-V's 200-watt ICAS Power Amplifier, the recommended power output levels are: 200 watts PEP for SSB, 100 watts for CW, 50 watts max. for AM/FM carrier power for short transmissions, 25 watts AM/FM carrier power for long winded transmissions, 25 watts max. for short burst digital modes (10 watts for long time-frame digital transmissions).

                          ATU / Antenna Tuning Unit & Outboard Tuner Cautions                                


How-to reduce the risk of damaging your FT-1000MP Mark-V series transceiver from its internal antenna tuner, or as some refer to it, auto-tuner:

1) Keep menu 4-3 (TUNING DRIVE) set to for 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. Practice has shown that the tuner has difficulty handing non-resonate systems and an SWR close to or greater than 2.5:1, especially so with the 200 watt FT-1000MP Mark-V. 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 200 Watt ATU; The topology of the design places the Auto Tuner Unit between the 200-watt PA and the QSK-T/R circuitry & ANT-A/B switching. In other words, the ATU only matches the 200-watt PA while everything else down-line (the Mark-V's QSK-T/R circuitry & ANT-A/B relays) will remain subjected to the station's feedline VSWR. There are advantages and disadvantages to this topology.

Disadvantage; Consider the case where a 2:1 SWR is presented by the antenna system, and the ATU is activated to match the 200 watt PA into the 2:1 SWR enabling full TX PO into the load. However, the 2:1 SWR remains present at/on the QSK-T/R & ANT-A/B areas of the circuit, and the components in those circuits must then deal with either higher than normal (200 watts into 50 ohms) RF voltage levels or higher RF current levels, owing to whether the 2:1 SWR is on the Hi-Z or Low-Z side of 50 ohms.

This is the Achilles heal of the design, the ATU will match certain loads that are dangerous to the health of the components in the QSK-T/R circuitry, risking destruction of those components. Many an operator has made the mistake of activating the Auto-Tuner's tune cycle into the incorrect antenna or an empty antenna coax jack, aka "open circuit" often with destructive results. To make matters worse, the now 18+ year old servo-driven ATU are failing intermittently and causing an increasing number of damaging "tuning faults". The commonly reported failure symptoms are high SWR with and without the ATU inline, loss of receive audio / RF sensitivity, loss of transmit output, most if not all of these --indicating a trip to the repair shop is in order.

In the interest of preserving the service life of the 200 watt Mark-V, it is highly recommended: DO NOT USE THE INTERNAL AUTO-TUNER. USE AN OUTBOARD TUNER where a tuner is necessary. This can not be stressed strongly enough. Yaesu no longer has the "proprietary parts" for the Auto-Tuner Unit thus rendering it non-renewable. All Mark-V rigs ship from my shop with the ATU set to "off" in user menu 8-8. ACTIVATE AND USE THE AUTO-TUNER AT YOUR OWN RISK, ITS YOUR RADIO. And be advised,"IF YOU ARE GOING TO PLAY, YOU ARE GOING TO HAVE TO PAY" sooner or later.


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, T/R, 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 wildly crank the knobs around on their outboard antenna tuner. Not a good idea! Such an incorrect technique is known to strain the Mark-V's QSK T/R switching. The QSK T/R switching is known to fault in certain situations, resulting in the destruction of components.

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 tweak the tuner. 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, high power "hot tuning" roller inductors is a concern for solid state transmitters. The problem being that the continuity of the aging roller inductor's moving electro-mechanical components seldom remain 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.

NOTE: This update can also be done (at nominal extra cost) with a precision plug-in micro-fuse for a "no soldering" easy DIY "in the field" replacement solution. 














DIY detail: Not visible as it is under the lamp, the copper foil circuit path between the lamp's two solder points is opened / cut.

Lamp specs; low power (about 1/2 watt) with up to a 14 volt filament. For lowest loss on 10 meters (receiver antenna path) my preference is to use 5 to 6 volt grain-o-wheat lamps with a 0.100 (0.125 max.) ampere filament rating when using just a single lamp, or 0.050 to 0.060 ampere filament when using a pair of lamps wired in parallel.


FT-1000MP Mark-V Field, the 100-watt AC/DC Mark-V

WA4GEG's Receiver protection ANT-A/B plug-in Micro-Fuse update


Available for the FT-1000MP Mark-V Field, a rear panel mounted receiver protection ANT-A/B plug-in Micro-Fuse modification. This update makes use of a precision machined aluminum "RF Shielded" micro-fuse holder with matching threaded aluminum cap. The modification is highly recommended for all Mark-V Field rigs used in multi-TX contest setups, for convenient in-the-field DIY serviceability. 

Pictured below, the micro-fuse holder is mounted in an already existing rear panel hole, that is normally hidden by a factory placed black plastic stick-on disk. The disk remains in place to camouflage the irregular preexisting square hole.















FT-1000MP Mark-V series transceiver's User Menu Settings


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 *SNR, set menu 8-4 to tuned.)

4-4         TX Audio DSP EQ                             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

To enhance SSB transmit audio the DSP may then be engaged. Suggested settings are as follows:

4-4        Transmit audio EQ         3
7-7        SSb-t                       150 ~ 3100 (Hz)

MIC GAIN control: With a good quality microphone, preferably a headset mic. for excellent VOX operating characteristics, a properly align FT-1000MP series transceiver will require no more than a MIC GAIN setting of 9 o'clock. Most often a setting between 8 and 9 o'clock is all that is required to attain ALC metering peaking toward the upper ALC scale limit.

PROCessor level control: When the speech processor is activated, a PROCessor level setting of no more than 10 ~ 11 o'clock will achieve excellent results without over compressing transmit audio into distortion. (Compression level peaking 3 bars on the COMP metering scale. -- assuming that the transceiver is in good alignment)

*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 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, specifically their models: LS-18A (for a single Mark-V), and the heavier duty LS-25A (handles a pair of Mark-Vs'). Details available on Astron's website here:

http://www.astroncorp.com/28vdc-linear-desktop

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. 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 power supply to enable operation of the transmit section's 200-Watt PA Unit.




FT-1000MP Mark-V & Mark-V Field notes


* Transceiver Frequency Readout Calibration; all transceiver's serviced receive REF Unit calibration (or TCXO) after a one hour warm-up period.

* VFO A/B intermittently resetting to 7.000.00 at switch-on is a common symptom. Those cases that are not related to a weak back-up battery are normally correctable with some minor repair work.



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