It’s been a while since I featured my FT-857 manpack on here and I’ve been using it well for over a year now so I thought I better show some sort of update.
So here it is. The FT-857 Manpack as it stands today…
The contents of the bottom front pocket, from left to right:
- 70W 19v Laptop travel charger with 2 pin, 3 pin and 12v plugs. Used to provide power to the battery charger.
- Various power connectors and 12V extension.
- Lifepo4 Battery charger and connectors
- H-250/U Military Handset
The contents of the top front pocket, from left to right:
- Spare fuses, battery monitor, velcro straps for 6M mast and small bits.
- 40M dipole with 1:1 balun and 12M of RG-174 coax. This will get me on any HF band by using the LDG tuner on the manpack but I’m moving to a linked dipole very soon.
- Garmin 60CSX GPS.
Compact 6M push up pole. This fits inside the main pocket and can be used as a vertical or as a support for the 40M dipole. It straps to the manpack frame with short velcro straps. It also fits inside the bag so you can walk around with it erected!
This is a switch box that I made up to allow use of the standard fist microphone or the H-250. The 3.5mm jack plugs into the radio when using the H-250 and passed the receive audio to the handset. You can still use the fist microphone to control the radio when using the H-250 handset.
The top of the manpack. The dual ratio UnUn is attached with velcro so it can be removed and placed remotely if needed. When used as shown, I connect the 6M push up pole (with a 6M wire inside) to the 4:1 or 9:1 terminal to achieve the best performance. When used with the 40M dipole, I disconnect the UnUN and connect the dipole to the socket on the front of the manpack.
This is a cheap fly fishing reel that holds 20M of 1.5mm stainless steel wire. The wire is marked every meter and 5 meters with different coloured nail polish. Just pull it out to the desired length and clip the flying ground lead from the UnUn on. Instant counterpoise…
The battery is a 8.4Ah LifePo4. It sits at 13.8v when fully charged and has a shallow discharge curve until it’s almost empty. I’ve used SLA batteries (not enough voltage to get the most from the battery and heavy) and LiPo batteries (Fully charged voltage too high so a diode based voltage dropper needed) but the LifePo4 could have been made for this application. It’s the perfect ratio of voltage and weight…
So there you have it. The manpack updated. It’s been in heavy use and these are the additions I’ve made along the way that have made it much more versatile and complete. With the antenna, mast, battery and charger all in the bag I can just pick it up and go. No doubt it will evolve again so keep your eye on the blog for more updates.