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Mobile Radio Shack Bag

There are times when I am frequently away from home base, usually either on the canal system or at a festival. During these times it’s very handy to be able to just grab a bag, without having to be concerned about sorting everything out.

This post will only detail the portable shack bag. The power supply kit that goes along with it with be detailed in another post.

The bag I use is an VHS Camcorder bag from the early 80’s. It’s very well built, & copes easily with the weight of all the radio gear.

Total weight for this system is 13.4lbs (6kg).

Mobile Radio Bag
Mobile Radio Bag

Above is the bag packed. Obligatory International Ameteur Radio Symbol patch front & centre. Being an old camera bag, this easily slings over the shoulder, with it’s padded strap.

Current Equipment
Current Equipment

Here is all the current equipment laid out. All the equipment to enable me to set up a station anywhere.
In the following photos I will go into the details.

Main Radio
Main Radio

First off, my main radio. This is the same Wouxun KG-UV950P mobile rig I have posted about previously. I have heatshrunk the power cable to keep it together & attached my standard power connector to the end. More on these later on.

HTs
HTs

In the bag I also carry three Baofeng UV-5R handhelds. Extremely useful for short range site communications, along with their charger bases. The charging base on the right has been slightly modified to support charging of my main LED torch as well, which uses similar Li-Ion based packs as the Baofengs.

Baofeng 12v Charger
Baofeng 12v Charger

As the charger bases for the Baofeng HTs take a supply of 10v DC, I have constructed a 12v adaptor system for them. (Which utter prat of an engineer at Baofeng picked 10v?)

Linear Amplifier & SWR Meter
Linear Amplifier & SWR Meter

Also included is a small Alinco ELH-2320 35W 2m linear amplifier. This was given to me from the local HackSpace in Manchester. (They don’t have any ham members, besides myself). Also here is my small SWR & Power meter, SDR kit & a pair of syringes. These are filled respectively with Copaslip copper loaded grease, (very good for stopping fasteners exposed to the weather from seizing up), and dielectric silicone grease. (I use this stuff for filling connectors that are exposed to the weather – keeps the water out).

Tools
Tools

I always keep essential tools in the bag, here is the small selection of screwdrivers which fit pretty much any screw fastener around, my heavy-duty cable shears (these buggers can cut through starter cable in one go!) and my trusty Gerber Diesel multitool.

Magmount & Pi
Magmount & Pi

Main antenna magmount & a spare Raspberry Pi.

Antenna, Patch Leads, Etc.
Antenna, Patch Leads, Etc.

Finally, the antennas for the HTs, main dual-band antenna (Nagoya SP-45) for the magmount, a small selection of spare plugs, sockets & adaptors. Also here is a roll of self-amalgamating tape, very handy for waterproofing wiring connections (especially when used in conjunction with the silicone grease), & a roll of solder wick.

Now, the main power connectors of choice for my equipment are Neutrik SpeakOn type connectors:

Neutrik SpeakOn
Neutrik SpeakOn

These connectors have many advantages:

  • They are positive locking connectors. No more loose connections.
  • They have a high continuous current rating of 30A RMS.
  • Relatively weather resistant.

Also, they have two pairs of pins – and as some of my bigger non-radio related equipment is 24v, this allows me to use a single set of plugs for everything. Without having to worry about plugging a 12v device into a 24v socket, and letting out the magic blue genie.

Once everything is packed up, here’s the bag:

Packed
Packed

Everything has a neat little pocket for easy access. Some closeups below.

HTs, Magmount
HTs, Magmount
Chargers, Amplifier
Chargers, Amplifier
Main Radio
Main Radio
Small Stuff
Small Stuff

I will post more about my portable power system later on, as this bit of my kit is being revamped at the moment.

Stay tuned!

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Moonraker SWR270 SWR & Power Meter

Meter Front
Meter Front

As I’m building up my radio shack, I figured an SWR meter would be a handy addition to my arsenal. This is a cheap Moonraker brand meter, which also will measure RF power. Above the front of the meter is shown, with the moving coil meter movement on the left, calibration adjustment on the right & the forward/reverse power switch.

Meter Rear
Meter Rear

For connections, standard SO-259 jacks are provided. The casing is sturdy 1mm steel. This is good, considering it’ll probably take a beating in my portable radio bag.

Directional Coupler PCB
Directional Coupler PCB

Here the cover is removed, showing some of the internals. The large PCB across the back is the directional coupler.

Directional Coupler Circuit
Directional Coupler Circuit

The SO-259 connectors are bridged with a transmission line, (the track covered in solder in the image below), while there are a pair of sense lines running alongside. This main line is electromagnetically coupled to the two smaller sense lines, which are terminated at one end with resistors, with diodes at the other to rectify the coupled signal.
The termination resistors are sized to match the impedance of the sense lines.
The diodes, having rectified the coupled RF, produce DC voltages representing the value of the forward & reverse RF power. These DC voltages are smoothed with the capacitors.

PCB Marking
PCB Marking

The PCB is dated 19-8-2011, so it’s a fairly old design.

Adjustments
Adjustments

Here is visible the back of the user calibration adjuster, with the factory calibration trimmer.

Meter Movement
Meter Movement

Back of the meter movement. This is a standard moving coil type. Nothing special.

 

This meter will soon be modified to accept connection of an external Arduino-based SWR & power meter, which I can calibrate individually for each band.
Stay tuned for that upcoming project.