Re: [Minimalist_QRP_Transceivers] Re: The beginings of my 40 meter DSB tranceiver

[Steve Smith]

I don't know about "solved" but he did increase the audio gain. That idea appeared several years ago in GQRP "SPRAT". I have yet to watch the whole video. Did he solve the T/R 'thump' in the audio?

S.S.

---------- Original Message ----------
From: "caulktel" <caul...@gmail.com>
To: Minimalist_QR...@yahoogroups.com
Subject: [Minimalist_QRP_Transceivers] Re: The beginings of my 40 meter DSB tranceiver
Date: Thu, 22 Nov 2012 02:08:08 -0000

It would seem that Peter has solved the audio issue. Check this out:

http://www.youtube.com/watch?v=mLCbnL5e_VA&feature=em-subs_digest

Joel
KB6QVI

[Steve Smith]

Hello Ben,

I have yet to decide what type of frequency element to use. 7200 KHz only allows about 75 KHz coverage of the U.S. phone segment (7125 - 7200 KHz) so I'll likely go with some combination of crystals in the "super vxo" arrangement as outlined by Peter in one of his videos. For my radio I would like to end up with an arrangement that uses two frequencies, each covering at least half of the U.S. phone segment, ~88 KHz. I may even employ a PTO but that isn't important right now.

7.2 MHz resonators are available from Mouser however they are SMT. I don't have any problem using SMT but some may. In the U.S., if you order just the resonator(s), tell Mouser to use USPS (not the default UPS) and to just drop the parts in an envelope. Much less expensive shipping.

I plan upon routing RF and DC from one side of the board to the other using aligned isolated pads. A piece of solid wire will tie the two sides together. Shouldn't need any coaxial cable if leads are kept as short as possible using careful layout.

I've never particularly cared for the LM386. Sure, it's inexpensive and simple to implement but I just have a 'thing' about it. Besides that, my philosophy regarding this rig (and most of the other stuff I scratch-build) is to, wherever possible, use parts scavenged from scrapped consumer electronics. So my entire radio will likely be all discreet components excepting any voltage regulator I might incorporate.

It is getting quite exciting to see all who are getting on board with this project.

73.......Steve Smith WB6TNL
"Snort Rosin"

From: Ben Pharr <b...@movl.net>
To: Minimalist_QR...@yahoogroups.com
Subject: Re: [Minimalist_QRP_Transceivers] Re: The beginings of my 40 meter DSB tranceiver
Date: Wed, 21 Nov 2012 18:09:29 -0600

So I've decided to go ahead and start procuring parts for the "Beach 40." I won't be able to start on it immediately, but maybe in two or three weeks.

What frequency resonator are y'all using? If 7.2MHz, where did you get it? I don't see one on Digikey or Mouser.

Also, any suggestions on where I might procure a variable capacitor for the VXO? This one doesn't look bad:
http://www.midnightscience.com/catalog5.html#part2

Steve, how do you plan on routing signals from the top of the board to the bottom? Coax?

Thanks,
Ben
WF5N