just for info: probably the best decoder is the SCS DSP-TRACKER. It will not just do digital signal processing on 1200baud, but impresses with multi-simultaneous decode on shortwave 300Baud and Robust Packet mode. It does also digipeat and Cross-mode-Gate, (from 1200baud vhf handheld to 300baud hf in remote areas), but lacks some other features of OT2 and cost are higher.. http://www.scs-ptc.com/shop/products/modems/tracker-dsp-tnc?set_language=en
----- Original Message ----- From: Lynn W. Deffenbaugh (Mr) To: [email protected] Sent: Monday, January 18, 2010 3:27 AM Subject: Re: [tracker2] The best tracker? David Hopkins wrote: > However few people voiced an opinion as to why one was better than the other. > I think the only comment was that a sound card is the best because > there is more digital bits available. > The Tracker2 was/is better than the original T2-135. As you observed, the difference was that the Tracker2 had an input filter that was lacking on the T2-135. However, there's a v1.2 T2-135 that dramatically improved the receive performance of the T2-135. I run 2 T2-135s embedded in Alinco DR-135s as KJ4ERJ-9 and KJ4OVQ-9. They work very well as trackers and I also use APRS messages to and from both of them both direct over RF as well as -IS to RF and back. I also run a TinyTrak4 on an iCom HT as KJ4ERJ-2/-7 as an IGate/WIDE1 digi. I like the decode ability of that device, but it does require more setup and seems to be more sensitive to the received signal deviation for decoding. The T2-135 "just works" when installed in the Alinco. W4SGC-9 is also a Tracker2 in the area that was originally on one radio (not sure which one), but is now externally connected to an Alinco DR-135. Right now he's having some receiving issues with that setup. I suspect he needs to tweak some levels in the OT2m to be compatible with the "data" connection on the back of the Alinco. As with everything, your mileage may vary. Lynn (D) - KJ4ERJ PS. You were correct about SoundCard decoding. In my experience, a properly leveled feed to AGWPEpro decodes more than anything I've compared it to. This includes the v1.2 T2-135, the TT4, and a Kenwood D7. The same radio feeding the hardware and the software still decodes more in the software. The deviation requirements of the software are much broader than the hardware.
