Date: Thu, 29 Apr 93 15:56:21 -0500 From: adams@chuck.dallas.sgi.com (Charles Adams) Message-Id: <9304292056.AA21634@chuck.dallas.sgi.com> To: qrp@Think.COM Subject: MXM Rig Gang, Jeff, AC4HF, i think i have the call right. asked about the new MXM rig, so in order to save time i'll give you a quick update and then a final review when i get it assembled. first: it's a transceiver, single band second: board is 4 1/2" x 3 5/8" (11.2cm x 9.2cm) third: uses the superRX receiver and transmitter from WA6IVC (Bruce) nice board with silkscreen. it's not green, but it goes inside a case anyway. ;-) the kit is not out yet, but will be shortly. i'll let you know. Bruce will be showing the rig at the Hamcom fest in June here in dallas area. the rig is vfo controlled, thus eliminating the previous problem of being crystal controlled. will work the whole band. can be set up for 80, 40, 30, and 20 meters. don't know if other bands are gonna be available for any time soon. kit doesn't come with cabinet and additional hardware (key jacks, power plug, etc.). this may be a turnoff for some people but not for the real hackers. :-) i'll shoot for getting it built this weekend or middle of next week. output transistor is 2SC799 and should be capable of 5 watts out. may run hot, but hey, silicon doesn't melt until the temp gets real high...... 72 de k5fo chuck dit dit p.s. rig to sell for $99.50 or so. definitely the hotest receiver around. 500 Hz bandwith with possibility of going down to 200 Hz bandwidth, but you'll probably get some 'ringing' at 200 to 100 Hz. uses Cohn filter in the IF. more details to follow. ciao, chuck ====================================================================== Date: Mon, 21 Jun 93 17:58:48 -0500 From: adams@chuck.dallas.sgi.com (Charles Adams) Message-Id: <9306212258.AA12553@chuck.dallas.sgi.com> To: qrp@Think.COM Subject: MXM Transceiver Gang, Jeff Gold(AC4HF), famous QST author and member of this group, periodically pings me about the new MXM simple transceiver. i've gotten mine in a case and going finally. too many trips and not enough room for equipment on the road to finish sooner. missed qso with the famous Jim Kearman. one of these days. i'll post final dimensions of the board, as i don't have them here at the office. the receiver section is the SuperRX plus an addition IF stage in the front end with Cohn crystal filter for 10Mhz IF followed by 455 Khz IF, thus a dual conversion receiver. bandwidth is about 500 cycles with the filter. i was on 40 meters early yesterday morning. i heard VE3s until about 10 am CDT. band was very long and signals pretty strong for this time i year, INMHO. lots of W1s and W2s on. i had mxm rcvr and icom 725, yaesu ft-707, and ohr spirit rcvrs on 40 meters. the mxm was the most sensitive. it heard signals the others did not. qrn was present as tropical depression was to the east of texas yesterday morning and some rain showers in northern part of state. the mxm receiver has more noise than the ohr spirit and about the same as the icom 725, which i consider a noisy receiver with respect to background noise levels. the yaesu ft-707 quieter but lacks some in sensitivity relative to the mxm. the yaesu ft-707 is a much better receiver than the icom 725. pluses for mxm rcvr - o good sensitivity o good stability o cheap o good selectivity minuses - o more difficult to align for the general builder, but not impossible just requires a little more time and effort on the part of the builder. i used the scope, frequency counter, and great care to align. but i do this with everything anyway. o a little more background noise internally o no RIT, but not a severe handicap to me transmitter is vfo controlled with osc for receiver and another mixer (NE602 mixer). i've got mine tuned to 500mW out into dummy load. with 2SC799 final PA, should be able to get 3 or more out. qsk without relay. a real plus to me. parts complement; 6 ics - 4 NE602s, MC3340, and LM380 6 transistors - 4 2N2222s, 2N3906, and 2SC799. 7 IF transformers i'd say the board is about 3.5 x 4.5. i'll just have to go back and measure it. more details to follow. ciao, "This is UNIX(tm)! I know this." - Lex in Jurassic Park in front of SGI workstation. Chuck Adams, K5FO - CW spoken here....70+ wpm adams@sgi.com ====================================================================== Date: Sat, 9 Oct 93 21:52:03 -0500 From: adams@chuck.dallas.sgi.com (Charles Adams) Message-Id: <9310100252.AA14256@chuck.dallas.sgi.com> To: qrp@Think.COM Subject: new MXM es R&R revies ... Here is the latest ad that came out today from MXM Industries, Rt 1 Box 156C, Smithville, TX 78957 (512) 237-3906 and I quote from the flyer that I picked from Bruce Williams, WA6IVC, owner and designer. I am not paid by or financially connected to MXM Industries, just a satisfied customer. ------------------------------------------------------------- Hi-Performance CW Transceiver Kit 80-40-30-20 Meters +----------------------------------+ | | | SIMPLE TRANSCEIVER | | | +----------------------------------+ Double Conversion Excellent Dynamic Range Super-Het Receiver Speaker Volume Audio Dual IF Filters True RF Monitoring Pass Band Tuning 3-4 Watts Power Output Double Balanced Mixers QSK Full Break-In The SIMPLE TRANSCEIVER is not a re-hash of an old design. It is new, inovative and outstanding. The receiver performance is the best of any kit we have tested. It rivals the sensitivity and selectivity of many of the expensive commercial transceivers. The QSK is smooth and you monitor your transmitted signal not some silly side tone. The pass band tuning feature will allow you to vary the effective filter width and the pitch of the received signal. The transmitter features a solid 3 to 4 watts output power with no chirps or clicks. It is also SWR protected just like the big radios. You kit will include: PRINTED CIRCUIT BOARD, ALL BOARD MOUNTED COMPONENTS, 7:1 VERNIER DRIVE TUNING CAP, ALUMINUM CABINET. You will need to pick up a few minor parts, such as connectors of your choice, from your local supplier or Radio Shack. $129.95 and $5 S&H Limited Time Only ----------------------------------------------------------------