FS: Maxtrac full band TX & RX Mod Kit

KF6HHS · Post by **KF6HHS** » Fri May 03, 2002 7:51 pm

I have for sale a full band modification kit for the 900 MHz Maxtrac radio. The TX section of the VCO will track in excess of 33 MHz, and the RX section will swing over 55 MHz. With the modification you can TX and RX any and all frequencies between 902 and 928 MHz. Forget about the concern of setting your repeater freq. above or below the 902.500 'pin shift' break frequency. The kit consists of one resistor and two varactors. The resistor change is in the PLL 'charge pump' circuit, and the varactors change out the existing tuning diodes in the VCO. No change to the present VCO tuning procedure, if you have already setup your VCO, the RX section will likely not require any adjustment, just change out the components with the ones in the kit. The TX VCO section will probably need a slight frequency adjustment. The modification will not affect any RSS parameters, including deviation. The stability of the VCO is better over temperature, and you will not see any ripple on the 'steering line' voltage near the band limits.

Kit is $15 plus ship, you can combine shipping on the kit and the Murata DFC3R915P025BTD drop in replacement filters ($10ea).

Regards, Hugh KF6HHS

Hrbcrb at aol dot com

njscan · Post by **njscan** » Sun Aug 18, 2002 6:42 pm

You have only one kit, or ??
I'm looking for a 900 Maxtrac and as soon as I find one I might be interested.
RSVP

Bob, WA2SQQ
Bergen County, NJ

KF6HHS · Post by **KF6HHS** » Mon Aug 19, 2002 1:10 pm

Hello Bob

I have put one aside with your name on it !

There is another approach to full band modification posted on the Batlabs site you may find of interest. It is based on a DC to DC converter circuit.

Regards, Hugh KF6HHS

Retired, now life moves at my pace...........

60hzEE · Post by **60hzEE** » Fri Sep 06, 2002 5:22 pm

Hello, Hugh.

I emailed you regarding purchase of several of your kits, but maybe it didn't reach you, since its been a while.

In anycase, would like to buy or possibly trade for a couple of your Maxtrac varactor kits?

Email with particulars.

Thanks.

Lee
60HzEE

PETNRDX · Post by **PETNRDX** » Sat Sep 07, 2002 9:57 am

Just a Plug for Hugh... I have used his kit, and it works great. This is the easiest "full band" mod I have found, and I tried several. The only challenge is working with small components (SMDS's), which you have to do with any of the mods I have heard of. This one is straight forward, and takes me about an hour. But I am lucky enuf to have an expensive solder/desolder station, and years of "foolin" with this stuf.

60hzEE · Post by **60hzEE** » Sun Sep 08, 2002 9:43 am

Thanks for the words of encouragement. I've done SMT components before, so not a problem.

Guess Hugh must not be monitoring this or his email.

Well, if I might ask a favor of you. If you have a way of reaching Hugh, I'd appreciate asking him if he still is selling his mod kits. I'd like to buy three for the 900MHz radios I have.

Lee
60HzEE