QNA:
Q - WHAT IS REQUIRED TO OPERATE THE AMPLIFIER ??
A - A 50 VDC at 50 AMP power supply is required. (2500 watt power supply)
Q - HOW MUCH POWER DO I NEED ON 6 METERS ??
A - Your exciter (transceiver) should be limited to 15 WATTS INPUT.
Q - WHAT IS THE NOMINAL OUTPUT OF THE HARRIS ??
A - Each platform is rated at 200 Watts DC. There are 4 platforms in each HARRIS module. These
     ratings are designed for 8 - 10 MHz bandwidth. SSB is 2.8 KHz.
Q - WHAT ABOUT COOLING THE AMPLIFIER ??
A - You will need 4 Radio Shack 28-1108, 120 MM, 80 CFM, 12VDC FANS.
Q - WILL I NEED OUTPUT FILTERING ??
A - YES, the BUD LF-601 is the perfect low cost commercial unit available. They are not manufactured
      now, but can be found on Ebay and/or QRZ. You can design and sweep your own. There are
      articles on the Internet with reference to home brew filtering above 54 MHz.
      Best solution: Find the LF-601.
Q - Is there any documents available regarding the Harris for Amateur Radio.
A - Yes, however there is no contact information available and I can not supply the source.

I wanted to mention that I have been questioned by local operators who for some reason insist that the HARRIS is not FCC approved for Amateur Radio use. I ask anyone to challenge the HARRIS design and note that the unit is FCC approved for commercial use and therefore should be acceptable under band allocation rules for Amateur use. I also want to point out that many of the VHF and UHF amplifiers that are "on the air" by Amateur Operators have never been FCC approved, in fact I wonder just how many HF amplifiers would actually be approved by FCC engineers.

Most of what you will read here will be HOW TO and not material subject to copyright laws. Don't look for SCHEMATICS, PART NUMBERS or TECHNICAL DETAILS...simple HOW TO USE material...only !!

Table of Contents:
(1) The BLADE SERVER SMPS by Hewlett Packard (50V @ 50A)
(2) The HARRIS requires 275 CFM of air across the HEAT SINKS.
(3) The BUD - LF601 Variable LOW PASS filter.
(4) The CONTROL head. What relays to use and how much will it cost to build.

The HP SERVER SUPPLY:
Part Number: 253232-001
RATING: 51 volts DC @ 57A, maximum values.
AC connection required: 240 VAC input 2900 W (15 AMP circuit breaker)
DC connection required: Negative and Positive leads 10 Gauge wire for amplifier connection
Power Supply Initialize: A digital pin-out connection to ground will be necessary to init the supply.

Follow the connections as shown above. Orient the screw to the LOWER RIGHT. The INIT connection
can be made using a FLOPPY DRIVE connector from an old PC power supply. Cut the RED wire and use Y/B/B. The DPDT switch will close the circuit YELLOW (9) and BLACK (11) to the center (10) BLACK.
HINT: I used shielded microphone cable from the connector to the switch.
Wiring the AC LINE IN should be done using number 10/3 600V Motor Cable. This is a soft cable with W/B/G in a black rubber jacket. The 10 gauge wire is stranded and can be soldered very easily. Connect as shown L = BLACK/WHITE and N = GREEN. Solder to the existing pins and then cover with CLEAR RTV.
Wiring the DC is a bit different. I soldered brass tabs to the existing pins and then soldered wires to the tabs. Brass strips heavy enough to carry this current are available at most hobby shops. You can wire direct to the pins by stripping the wire and creating a "Y" to form a connection. This works fine but no matter which connection you choose, remember to keep these leads short as possible. You may wrap the leads in an RF choke (toroidal core) and suppress SMPS noise using .005 or .1 caps across the DC LEADS. The power supply should look similar to the above when ready to use on the HARRIS. The POWER SUPPLY will emit a GREEN LED when it is ready. Try not to block air flow through the fans located in the front. This power supply, properly used in this service (SSB) should operate, like the amplifier itself, cool and quiet. There is a life span of many years here if you operate within specified parameters.  
The image to the right shows the PIN OUT connections I used for the DC power connections.
The HP power supplies are available from several sources. They can be found on E-Bay for as little as 30.00, but beware that some of these units do not have any type of a warranty. Spend a few dollars more to protect the investment.
I have also heard that there are a few transformer type power supplies that will handle the 50 AMP requirement. These will be heavy and require a lot of energy to operate. Using a SMPS is recommended.

Cooling the HARRIS:
Cooling is one of those problems that may require some mechanical structuring. Each heat-sink (4) on the amplifier is located over a platform. Each platform delivers 200 watts of RF power. I suggest to following design. It works well and can be built for under 50.00 using new fans available locally.

The Radio Shack 28-1108 12VDC Ball Bearing fan is whisper quiet and yet it blows 80 CFM (or 320 CFM) across all four platforms. You can build the container using 2 - 1 by 1 by 20" aluminum angle stock. Attach the rails and the fans with 3/16 by 6 inch all thread rods placed between fans 1/2 - 2/3 and 3/4.
Do not over tighten, this will distort the fan mount and cause rubbing on the case. Wire these using the connectors supplied and connect to the same 12VDC source that you will use to operate the ANTENNA CONTROL HEAD, shown later in this series. These fans work great and they essentially cover the entire heat-sink. I have thoroughly tested this configuration and I have never seen the temperature above 80 degrees Fahrenheit.
HINT: I purchased a small IR Thermometer. They are cheap and can be found at any tool store.
There is not much you have to know about this installation, just be sure you have the FANS ON before and after applying juice to the amp.

Output (input) Filtering:
The HARRIS might need some OUTPUT filtering if you plan to run the amplifier on FM. This unit will certainly play well but there could be some nasty (but controllable) 2nd and 3rd harmonics. Remind you they will be very clean and on a spectrum analyzer, they will be sharp and defined. EXAMPLE: 50.125 = 100.25, smack in the middle of the commercial FM band. The THIRD will radiate on the MOBILE RADIO allocation just above 2 METERS. This harmonic will not be a problem if you are powering your Harris into a well designed antenna.

The use of a filter is explained in the ARRL Handbook. There are a few HOME BREW articles from QST and the ARRL handbook. My main concern is POWER handling capabilities, and the BUD is rated at 1200 watts. I am running the BUD-LF601 variable LOW PASS and I am strictly on SSB so my 2nd harmonic must be considered. I do not filter the TS-2000 output, only the HARRIS output after the amp and before the control relays. I have checked the 2000 for harmonics and my results are conclusive, at 10 watts max, I am not to worry about the input to the amp.
These BUD units are hard to find and a clean one like above will bring 50.00 on E-Bay. I plan to check the settings after I sweep the filter. I will give you the final settings and even supply a schematic and coil information, if you want to roll one on your own. For your information the length is 12 inches total not factoring the PL-259 connectors.
HINT: If you experiment, have fun, but if you are more-or-less into plug and play...find a BUD-LF601.
I f you would like a copy (.PDF) of the United States RADIO BAND allocation chart, click here. Save the document to your computer. This is a LARGE CHART and should be increased in size to read the information correctly.

The RELAY CONTROL box:
Putting the HARRIS to work will require some control circuit and antenna relay switching. If you are not as proficient as others in modifying commercial equipment, I suggest you leave the amplifier alone and concentrate on an external relay control head.
REQUIREMENTS:
(1) 6" by 4" by 4" (minimum) aluminum BUD box.
(2) A 12 VDC relay set:
        (a) 2 - GIGAVACS (SPDT) and 1 - DPDT Switching relay. (MAX GAIN)
        (b) 2 - Gaurdian DPDT Glad contact switching relays (*). (HENRY RADIO)
        (c) 1 - Magnecraft, P&B or equivalent 3PDT HD switching relay (sets 3/8" apart). (RF PARTS CO.)
        (d) 2 - as above "C" that use DPDT configuration.
The relays and the RF connectors may be purchased at: Max Gain Corporation, Henry Radio or RF Parts Company. Small items from local RADIO SHACK (along with the fans).
The GIGAVAC relays will cost you 170.00 for the pair. These are vacuum relays and will be your best choice.The Gaurdian relays will cost you 100.00 and a set of Magnecraft or P&B will be around 75.00.
(2) PL-259 connectors (female). (Radio Shack)
(1) "N" chassis mount connector (female)
(1) "BNC" Chassis mount (Female) (radio Shack)
(2) RCA Phono connectors. (Radio Shack)
(1) SPST miniature switch. (Radio Shack)
(1) 12 VDC Power Connector. (Radio Shack)


This is the original control box I built first. The relay was a RADIO SHACK 3PDT antenna relay, but I do not believe it was capable of carrying the RF delivered by the HARRIS.
The layout is similar here but the image below will show you the Gaurdian relays installed in another unit I built. The schematic is also available on this page. Note that I chose to SHORT the HARRIS output to ground on the GAURDIAN and the MAGNECRAFT relay. I will explain the relay sequence later in this section, however note that I found the GAURDIAN relays worked best for my application.
The common design for antenna switching is to bridge the NC contacts to each other. This is fine but the HARRIS is a fast attack Solid State amplifier and switching the exciter into the HARRIS before the amplifier sees a 50 OHM load may damage the finals. The HARRIS should see the antenna before the exciter is energized. This is sequencing. This also eliminates "hot excitation" of the amplifier and will be noticed at the exciter output if the exciter is fired to early. Don't get technical here, simply follow this rule: "The HARRIS must see the antenna before the exciter input is turned on." That is all you have to be concerned with. If you have an ARB-704 Ameritron controller, use it.
The Gaurdian relay controller is shown here as completed and in use by K3HKR. All lines for PTT and AMP INIT are clearly marked. These are RCA phono plugs and they are center to chassis ground wiring. The Gaurdian's are protected with diodes and as you can see all leads are short as possible and shielded where required. In order to use a pair of Gigavac relays, you will need a DPDT relay in addition to control the AMP INIT line. The Gigavac relays are excellent and have a very fast open/close function. They are vacuum and will more than handle the 1500 watts PEP from the HARRIS. The Gaurdian relays are rated at 2KW PEP and they too will handle the amplifier. The Magnecraft relays are also rated at 2KW, depending on the models you choose. In both units SW-1 controls the 12 VDC applied to the relays. This affords you a STANDBY mode that does not initialize the amplifier.
        
The schematic above shows the relay requirements:
The INIT LINE is pulled to ground, the NC contact is not connected (standby).
The "E" - exciter input via a PL259 is connected to the COMMON relay connection (RL1). The NC contact is bridged to the "A" - antenna connection. That is the NO contact on the output relay (RL2). The "O" - output from the HARRIS is fed at COMMON (RL2) and in the NC (standby) position is chassis ground.
When energized, the INIT relay closes, both RF control relays close. The exciter output is sent to the "H" - HARRIS input via the BNC connector. The "O" - HARRIS output is sent to the antenna via the NO contact at "A". In this configuration, no RF power can reach the exciter input. When the PTT is open, the RF "O" (N connector) output is grounded and any residual energy is returned safely to the chassis.
The input is 12VDC and SW-1 controls the PTT circuit energy to the relays. This should be wired in the GROUND side of the relay coil/s.
The picture here shows you the HARRIS along side my Henry 3K-A. The stand is home brew, but Tractor Supply and Harbor Freight sell a roll-about tool stand that is perfect for the amp. You can hang the power supply below the amp. The FANS are powered by the same 12 VDC that you will use for the control head.
The balance of the connections are shown below. The slide-on "N" cable jumper that should have been supplied, may be attached using the small KEY, I designed and illustrate here. Use a 1/4 inch by 1 inch bolt and nut through the hole next to the "N" connector. This is a guide hole for the HARRIS AMP RACK. There are four of these holes in the back of the amp. Use this one to bolt the KEY onto the amp and secure the cable in place.
      
The POWER CONNECTOR (on the right) plugs into the rear of the HARRIS. Not everyone has one of these, but they are available. Contact the person who sold you the module. The connections should be easy to understand and the use of an RCA phono jack here makes it simple to disconnect the amplifier when required. These connectors have a BNC input line prewired with a MALE or FEMALE connector.

That about covers most of the installation. Remember no more than 15 watts input !! Be sure you use a good 1.5:1 or less antenna and find a BUD LF-601 filter as soon as possible. I will have the filter details here soon. You can build one as described in the ARRL HANDBOOK, but without access to a spectrum analyzer, you may just waste your time. If you follow the settings I offer, you will enjoy the HARRIS on 6 meters. Remember that the MIRAGE 100W 6 MTR. BRICK has a MSRP of $389.00 less power supply. If you think $500.00 is a stout investment to operate the HARRIS, think again.

Have a blast...I will be listening for you.

COPYRIGHT 1/10/2010 - THE MATERIAL LISTED ON THIS PAGE IS COPYRIGHT AND MAY NOT BE COPIED FOR COMMERCIAL USE IN ANY FORMAT WITHOUT WRITTEN PERMISSION FROM K3HKR. THIS INFORMATION IS OFFERED AS INSTRUCTIONAL REFERENCE ONLY. ANY ONE USING THIS MATERIAL WILL DO SO WITHOUT ANY CLAIM TO THE AUTHOR. IF YOU ARE NOT CAPABLE AT THIS LEVEL OF EXPERTISE, DO NOT ATTEMPT THESE MODIFICATIONS. SEEK PROFESSIONAL HELP.
CAUTION - THE VOLTAGES ATTACHED TO THESE DEVICES ARE LETHAL. YOU CAN BE KILLED.