DRA818V + Minicircuits Low Pass Filter.

The DRA818V

I wanted something small and almost disposable for APRS tracking.  The DRA818V fits the bill but needs low pass filtering.   Some photos of the prototype boards and output floor while TX outside intended band.  The SMD filter works great, inexpensive, and makes for a nice package.  I used a Mini-Circuits LFCN-160+.  The DRA818V can be found on Ebay.  OshPark manufactured boards I designed in KiCad.

DRA818V Filter

Prototypes

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METCAL Models, Tips, n Tricks

If you are in the market for a soldering station you can’t really go wrong with MetCal.  The are dependable and easy to repair should something happen.  Instant heating, well placed heat, and an easy to use hand piece are just a few of the reasons to use an inductive RF soldering station.  New stations have come down in price and units from Thermaltronics are compatible.

Big issues are if you haven’t seen one or not generally “in the know”, finding used units that are usable can be difficult.  First, to have a working, station you will need 3 main components.  Below is a list of recommendations about how to get everything together.  I’m sticking with the high end industrial models and not the smaller units.

Power Supply / RF Unit

RFG-30 – These are the oldest MetCal in this series.  Good units.  No auto-shutoff. Has one LED Light

PS2e-1  – These are the next version with Auto-Shutoff.  Please note that these were produced in 220V and 110V. You want a -1 or -01 unit for 110V. Has 2 LED Lights.

MX-500 – These are one release behind current.  They offer two outputs but you can only use one at a time.

Hand Piece

Any MX-500 Hand piece will work. MX-RM3E

Newer Metcal MX-H1-AV

Thermaltronics – SHP-1

Stand

You will want either the MetCal Stand or the Thermaltronics.  They have magnets built it to keep tip cooler when not in use.  SHH-1