FT-1000MP Mark-V series notes

FT-1000MP Mark-V series


FT-1000MP Mark-V (200 watt)

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

FT-1000MP Mark-V (200-watt version): 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. In the event of the aforementioned faults, the fuse lamp will burn open effectively disconnecting the antenna path to, and protecting from destruction, the receiver’s front-end (RF Unit Board) and the receiver’s vacuum-reed T/R antenna relay.

This modification (or the Micro-Fuse mod; see Note below) was automatically applied to all Mark-V’s serviced in my shop for decades. The fuse lamp will also burn open and protect the receiver front end from dangerously high RF levels from a nearby transmitter, high-power mobile unit, proximity lighting, etc.

NOTE: An alternative to the soldered-in-place “fuse-lamp” has been applied to many Mark-V rigs for those without soldering skills, or that simply prefer a plug-in replacement solution. On those rigs a plug-in micro-fuse was fitted in place of the “fuse-lamp”, the LittelFuse p/n 0273.125 spec’d at 125 mA, the version with 5mm leads. Spares are available for order @ $5.00 each + $2.00 postage. To order replacements contact: wa4geg [AT] gmail [DOT] com and type MICRO-FUSE in the subject line. 


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 the 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; ICAS 200 watt PA & Class-A Cautions                                

Many an operator has fried the final stage output RF power MOSFET (transistors) by using the Mark-V PA’s (Power Amplifier) Class-A mode as a convenient way to limit TX-PO to 70 watts for key down antenna tuning etc. Long-duration Class-A operation (key downtime) 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, but rather the ICAS heat sink design, which does not have the recommended 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 (Intermittent Duty Cycle) RF Power Amplifier, history has proven these recommendations: Use 200 watts PEP or less for SSB voice, 100 watts or less for CW taking care to limit “tuning up” keydown time to no more than 5 seconds (when running 100 watts output). Use 50 watts maximum AM/FM carrier power for short “break-in” transmissions, 25 watts AM/FM carrier power for long-winded transmissions, 25 watts max. for short burst transmissions on digital modes (10 watts for long time-frame transmissions).

200 Watt PA MTBF service life example: I know contest operators that manage to get from 10 to 15 years out of a set of “finals” (RF power MOSFET output transistors) while other operators with a “heavy foot” manage to blow their finals after only a year or two. On the other hand, others have over 18 years on the original set of finals in their Mark-V (200-watt) transceivers, operating only SSB voice at 100 watts of power output.

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

In the course of servicing, and properly aligning 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 are 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 aligned 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, a 28VDC linear power supply is an excellent choice, provided the Mark-V is operated at 150 watts maximum SSB PEP output, yet again an excellent idea for increasing the service life of the “final” RF output MOSFET/transistors.

Power supplies fitted with a front panel current limit adjustment may be set for 16 ~ 18 amperes of limiting, which is not critical since the Mark-V itself has internal current limiting (ALC) for its 200-watt PA Unit. One supplier for 28 VDC linear power supplies is Astron, which manufactures rugged RFI quiet “aka noiseless” linear regulated classic “heavy iron” transformer-based units, and one of particular interest is their model LS-18A. Details available on Astron’s website here:


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


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 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 VDC power supply to enable the operation of the transmit section’s 200-watt PA Unit.

                          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 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. Practice has shown that the tuner has difficulty handling 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 load 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 subject 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 heel 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 the 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 ATUs 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, and 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 the user menu 8-8. ACTIVATE AND USE THE AUTO-TUNER AT YOUR OWN RISK, IT’S 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 bulletproof! 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 faulty 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 the 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 is that the continuity of the aging roller inductor’s moving electro-mechanical components seldom remains optimum, particularly while the roller is in motion. SWR spikes occurring while tuning roller inductors are a known cause for damaging solid-state transmitters, to say the least.