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A search on eBay has thrown up lots of useful RF transceiver modules, not as low cost as the AM ones found by G6ALB, but nonetheless very low cost and suitable for local communications, Some are 100mW and some 500mW or 1W.  The ones I saw were data units, but these should be suitable for speech  with simple mods. I am unclear how some of these are programmed to the correct frequency. There is usually a choice of either VHF or UHF and I think some are essentially FM.

Put  “UHF transceiver module eBay” into Google to see what comes up. Or try “VHF” instead of UHF. I was amazed how low cost these were.

Well designed DSB transceivers are much simpler than SSB rigs as no SSB filters and mixing to final frequency is needed. They must not be over-driven to avoid a spreading signal. The PA needs to be linear too. These issues being carefully considered, you end up with a rig that has the same bandwidth as an AM rig but with a suppressed carrier. DSB transmitters are usually received as an SSB signal. The downside is that if a simple direct-conversion receiver is used then there is no rejection of stations sitting on the other sideband. So, they are best on quieter bands, rather than busy HF bands. Bands like 10m, 6m and 4m are probably good candidates.

Although not impossible, it is quite difficult to demodulate a DSB signal on a simple direct-conversion receiver. DSB rigs are ideal as simple transceivers to communicate with SSB rigs.

See http://home.alphalink.com.au/~parkerp/projects/projmicro40.htm

Also: https://aa7ee.wordpress.com/2013/10/19/the-vk3ye-micro-40-dsb-transceiver/

See http://www.phonestack.com/farhan/minima.html

This is the latest project from Ashaar Farhan. Component cost is said to be less than $100. This is based around a Si570 sythesiser and a programmed Arduino micro-controller IC. It looks a simple to duplicate rig covering up to 30MHz. It is the successor to the BITX rig I think. The IF is 20MHz. If you only want 0-15MHz or 15-30MHz (i.e. not both) the rig get even simpler.

As it stands it produces 1W pep but it is easy to add a further PA. 

Although a kit of parts is available, I am not aware of a full kit with enclosure and a PCB being available as is the case with the BitX from Hendricks Kits.

This looks like a design by Michael Rainey AA1TJ, but this one was on a German blog site of Peter DL3PB. I was very annoyed by the Facebook pop-up that kept appearing. I kept closing the pop-up but it is really annoying. Website owner – PLEASE get rid of it!

See http://streampowers.blogspot.co.uk/2013/08/para-saki-qrp-transceiver-fact-diodes.html .

The design makes extensive use of tunnel diodes, a Michael Rainey favourite.

The first UK price looks like around £999 from Nevada who expect stocks spring/summer 2015. This is more than I was expecting.

This image is the best I could find. The image is located on the Universal Radio site in Ohio and the link to the image will be removed if this is a problem.

http://www.universal-radio.com/catalog/hamhf/3991lrg.jpg

I would consider investing in this transceiver, but would be looking for a better price. The FT450D is currently £699 in the UK (even less at MLS £619.95 according to G1KQH) I wonder if they will spin out an FT817 replacement based on the FT991 design? I am sure there would be a good market for a 5-10W version here in the UK.

G1KQH informs me this Chinese transceiver is available for an introductory prce of £399.99. Personally I think this is MORE than I would expect. To me it still looks like a “back shed” design. I notice this supplier has sold out.

See http://www.sinotel.co.uk/index.php?main_page=product_info&cPath=20&products_id=183&zenid=oi6qsdgfla6p73q0c5vhs40kj3 .

This is an introductory price for the basic version without TCXO and noise blanker. The FT817ND is now available for well below £500 with cash back offers and, to my mind, is a well proven MF-UHF design.

The X108 claims ” minimalist industrial design”. Read NO industrial design in my book! Still waiting for the Chinese “killer” radio to out-smart the Japanese. This, in my opinion, is not it.

G1KQH has told me that the 9-band multmode transceiver, the X108 from China, can now be ordered on-line.

http://www.wouxun.us/item.php?item_id=346&category_id=65

Personally, I’d prefer the FT817 but, even with shipping to the UK, taxes and duty , the price is attractive, even if the product looks rather ugly (to me). It still looks “back shed” design to me. Personally I’d rather wait until the Chinese are really there with their designs. Others may disagree, but the industrial design of this product certainly lets it down.

Also, this is a kit, but with very little soldering.