Ham Radio


The N8MH Shack

Digital satellites have been my passion since about 1990. Current equipment in the shack includes a TS-2000X (modified for 38k4 packet) and a "heavily modified" TS-790A (it too is used for 38k4 packet).  TNCs include the TAPR DSP56002EVM, the AMSAT/TAPR DSP-93, a Paccomm PSK-1T, and a couple of Paccomm Sprint-2 TNCs.  Other rigs in the shack are an FT-817ND, an IC-R1500 receiver (the PCR-1500 with control head), an IC-W2A, and a Kenwood TH-F6A. I operate satellites on modes U, V, L, and S.

A recent addition to the shack is a Funcube Dongle.  It's a 64-1700MHz SDR receiver in a thumbdrive size case! what a neat piece of hardware by Howard G6LVB.

You might see my homebrew track box, called SAEBERTrack, on the top shelf. It was the result of several years of building and designing trackers with my elmer Gene, KC4SA. The name SAEBERTrack came from a combination of his call (SA) and my former call of KC4EBR (EBR). The second generation tracker has been in service for nearly 11 years now. You can read about SAEBRTrack by following the in the section down the page.

I've been using an LVB Tracker for the last several months.  It works wonderfully.

Look for me on AO-51 and AO-27, FO-29, AO-7, or VO-52!

73 de Mark, N8MH  




If you looking for the SAEBRTrack antenna controller project, following this link:

SAEBRTrack webpage

Installation pictures of the Symek IFD board in my TS-2000X

A collection of some photos I took during the installation of a Symek IFD board into the Kenwood TS-2000X can be viewed here

The Symek IFD board provides an IF tap so that high speed packet opertations are possible at 38k4 (and presumeably up to 76k, although I have no means of testing out my setup at that speed).  Operations on AO-51 have demonstrated that this setup works quite well at 38k4 speeds! 


ARISSat-1 Telemetry and the Funcube Dongle Pro

testing of big file hosting 

New OLED Display for the AMSAT LVB Tracker!

Wow, thanks to volunteer construction guru Mike Young, WB8CXO, the ever-popular AMSAT LVB Tracker has a new look!  The OLED displays are simply amazing. Can see it from any about viewing angle, and it's so crisp and clear.  On sale at Dayton Hamvention 2013!!

Landwehr 70 cm Preamplifier Photos

I bought a pair of used Landwehr preamplifiers (2M and 70 cm) a while back.  When I finally got around to connecting the 70 cm unit, it exhibited a strange result--when powered, noise increased, but the signal did not; it was essentially buried underneath the noise.
I took the cover off and applied 12V, and the two relays closed----or did they?!?

One side looked good, while the other side didn't quite push the "little white button" enough to make the contacts meet. It was stuck--just a gentle push with the finger, and I could tell it had become "unstuck." Inserted back in line, and bingo! It's working just fine.

I have resisted my urges to spray something down in there...figure I can unstick it the same way another time, should it happen. Looks like the preamp was made in 1990, based on the dates of the relays.

What I was seeing seemed like it might be a relay issue on one side (could hear a rise in noise, so the relay at the output side (rig) was working--but the relay on the input side (antenna) wasn't. So, when powered, the input relay didn't switch over correctly--what I was seeing now makes sense!

Anyhow, it wasn't the GaAsFET after all.

Here are some photos:











AO-51 AMSAT Echo Telemetry Decoding

Decoding telemetry from AO-51 requires the installation of two software packages/files.    Below are instructions as written by Mineo Wakita / JE9PEL, but with my edits to the file links and a few other tweaks:

First, download "TlmEcho Ver 1.04" which contains the complete windows installation
package from (1) below and install it in your PC. 

Second, you download the new version "TlmEcho Ver 1.1.1" from (2) below and extract it in the same directory (typically C:\TLMEcho) as the original installation above.  You will need to overwrite a few existing files, including the Tlmecho.exe file.

Third, be sure to edit the CPBINI.txt file for com port, com port speed, modem type, KISS ON/OFF parameters, callsign, LAT/LON, etc.

Most users experiencing trouble have forgotten one of the above steps and/or have issues with getting their TNC into and out of KISS mode.  Check those likely suspects first!

Happy telemetry collecting! 


Mark N8MH

Mike Kingery, KE4AZN has written a telemetry decoder, TlmEcho,
that will allow the user to view and capture telemetry that is
downlinked by Echo in real time.

(1) Complete windows installation package
    TlmEcho Ver 1.04 installation package


(2) Executable file update
    TlmEcho Ver 1.1.1 upgrade files