N7NEW 2 Meter VHF Portable Repeater
Used for Emergency Repeater or Event Repeater
This is a completely self contained Emergency Repeater.
145.130 (-600) PL tone 131.8 set at about 45 watts
Load it in the back of a vehicle and haul it to where ever it is needed, hook it up to a 12 volt battery, plug in the Antenna and it is on the air.
The ant mast slides into a bracket on the corner of the job box and you just tighten the thumb screw to keep it there.
If you fasten the ant mast to something else, you don't even need to unload the box out of the vehicle.
If this repeater is needed for an event or you have questions email Mike at N7NEW
Thanks to WA7HTJ, W7GLB & W7HNH for all their great help!
W7GLB Silent Key
Having a need for a portable repeater I decided to build one.
The Cle Elum & Ellensburg Ham Clubs have many events that they do communications for over the summer months.
One of which is the Cascade Crest Classic Ultra Marathon.
We tried cross-banding and it worked fine except for the normal problem of people doubling because of not being able to hear each other.
So we started thinking about a portable repeater.
I decided to use one of the SNP (shared non protected) pairs to avoid Coordination on both sides of Cascades.The PA board in this radio puts out over a 100 watts.
We have it turned down to about 45 watts and have had it up and running almost continuous for 48 hours at a time without damage.
I installed three 2" fans on the PA cooling fins.
We built up the repeater out of...
GE MASTR II Mobile radio free from WA7HJR & W7HNH
"Wacom" WP-639 = TPRD-1554 148-174 MHz Pass-Reject Base Station Duplexer $150.00
Channel Elements: International Crystal Manufacturing Company, Inc. (ICM) $49.99 each
Controller: NHRC-4/M2 MASTR II plug in controller board $189.00NHRC-VSQ MASTR II Internal Volume & Squelch controls $10.00 HRC Shipping +$16.00 Communications Specialists TS-64 DS Tone board $57.95 Communications Specialists Shipping $8.01
Ant Diamond CP22E $62.9512 Volt Marine Battery $64.00
Rigid Job Box $179.99Miscellaneous Capacitors, Components, connectors & Cable about $100.00 New 3/28/2010
Five 6-32 Ferrite Slugs for GE Mastr II PLL Exciter Conversion $17.00
One New PLL Channel Element: International Crystal Manufacturing Company, Inc. (ICM) $59.45
Total about $1014.35
The original Mastr II Mobile radio wasa MX76KKS66C
We Modified the receiver Osc/mult board to make it a low band per GE specs. Then found a dead stage in the IF board. Changed that board out and the receiver sensitivity came down below .5 micro-volt.
My board = 19D423241G4 Rev F
C 407 from a 12 to 15 pF
C 412 from a 5 to 8 pF
C 417 from (unknown value/maybe not installed) to a 3 pF
C 421 from (unknown value/maybe not installed) to a 18 pF
After getting the receiver tuned up, we worked on the PA board. It had some problems so we swapped it out for a good one. When turned up it put out 120 watts. Set the output to 40 Watts. We set the levels and called it good to go. After that I made the mods to duplex the Mastr II per MASTR 2 Infosite instructions.
The NHRC controller went in like clockwork as did the Communications Specialists TS-64 DS Tone board. Added the NHRC-VSQ MASTR II Internal Volume & Squelch control at the last. Hard wired a speaker after cutting the control head cable shorter.
W7GLB modified the Wacom Duplexer and tuned it up for me. Had to change Cable Harness to right lengths to get it to tune to 144.530/145.130.
New Improvements 3/28/2010
Remember, this is on the 2M ham band, (low end)... changed the slug in the VCO coil to ferrite. It was aluminum and placing a ferrite slug in the coil form will lower the resonance, allowing better PLL lock, especially in cold weather.After testing the repeater out for some months at various events, I found that the PLL board would not lock every time. Ordered up a ferrite slug for the VCO coil (Repeater Builder) and replaced the aluminum one with the new ferrite slug. Also sent in a new Icom (International Crystal Manufacturing) for crystal cut & temp comp for the PLL board. Installed both and tuned up the VCO coil 3/28/2010 with Bobs help. Set VCO voltage to about 5.64 Volts.
Where to buy the ferrite coils... 6-32 Ferrite Slug for GE MII PLL Conversion
Have had the Repeater on the air here at the home QTH for 3 months using it locally.
Have not had one problem with it since changing the VCO coil to ferrite.
It has worked flawlessly.
Used the Repeater for the Cascade Crest Classic 100 mile ultra over the weekend.
Turned it on 8/27/2010 Friday night at about 9:30 PM and it ran continuous until
8/29/201 Sunday 4:00 PM without a glitch. I am real happy with it.
By the way a new course record was made this year... 18 1/2 hours for the winner.
Report August 25-26 2012
Used the repeater for the 2012 Cascade Classic 100 mile Ultra Run.
It was on the air from Friday late afternoon until late Sunday afternoon.
It worked flawlessly.
Used the repeater for Bothell HAM-CERT-Fire-Police-EOC-Schools-retirement homes exercise for 2012.
Repeater was up and running on battery power with no problems for this emergency exercise.
Here are a couple of pictures taken at the drill & one showing the way the repeater was set up but from earlier practice drill. (both at Fire Station #44)
Below is a picture showing VCO Voltage TP
Pictures of Repeater
Picture showing NHRC Controller board & Volume/Squelch board
Picture showing Communications Specialists TS-64 DS Tone board mounting.
Pin out for TS-64
Maiden Voyage to be August 29/30 2009.
Will let you know how it held up.
August 31 2009... Well the repeater did a great job. It had only 2 glitches. One was Saturday Night about 9:30 PM and the other was Sunday morning about 10:00 AM.
Both times it was the same problem and only lasted about 2 minutes each. The phase locked loop quit locking for a couple of min. The first time it started working again before I got the lid off the radio. The second time I had time to adjust it a smidgen. It did not fail again after that. Will be checking that out further right away.
Here are some pictures of it's maiden voyage on the 2009 Cascade Crest Classic.
We were located near the center of the 100 mile course on Amabilis MT. at about 4500'
Amabilis as viewed from Thorp Mt. Thanks Glenn !
Cascade Crest Classic Aid Station Sites as viewed from Amabilis Mt Repeater site.
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