"Bella" An 80m Transceiver by AA1TJ
Some time ago I was approached by Jack Ward, curator of the online Transistor Museum, with the imaginative notion that we should attempt to build and operate an amateur radio station using the earliest available semiconductor devices.
http://web.archive.org/web/20101124023733/http://aa1tj.com/Bella.html

"Menos es MAS" 80m Transceiver for 2010 MAS by AA1TJ
The heart of the transceiver uses seven components. The bandpass filter (shown at the right on the circuit board) uses another seven components; although MAS rules only penalize me for three components in the output filter.
http://web.archive.org/web/20101124023153/http://aa1tj.com/Menos%20es%20MAS.html

"Mikums" An 80m CW Transceiver Using One Tunnel Diode by AA1TJ
It occurred to me that the keying technique used in my Reggie transceiver would provide an excellent solution to the problem of keying a tunnel diode transmitter. The result is Mikums; a one-active-device, 80m, CW, transceiver built around a single tunnel diode.
http://web.archive.org/web/20110619022514/http://aa1tj.com/mikums.html

"Reggie" A One-transistor 80m CW Transceiver by AA1TJ
Reggie is a one-transistor, 80m, QRP transceiver designed for the minimalist. It's a "dual-action" QRP radio; not only does it transmit a small signal, but the receiver converts every signal on the band into QRP.
http://web.archive.org/web/20101124023827/http://aa1tj.com/reggie.html

1 Volt transceiver for 80m CW by OH1TV
I had earlier built keyers using 1.5V battery as a power supply. Next challenge was to try to make the whole station using 1.5 Volt batteries as power source. Designing circuits, which work with that low voltage was my motivation for this project.
http://www.kolumbus.fi/pekka.ketonen/1V%20transceiver%2080m.htm

3.5MHz 5W CW Transceiver by JF1OZL
I operated 3.5MHz SSB for two weeks. But 10W SSB was too weak to make CQ by myself. 3.5MHz band is very noisy in Japan. Therefore I decided to make and operate 3.5MHz CW with QRP.
https://www.emilio.com.mx/jf10zl/35mcw.htm

4.5W one transistor transmitter for 80m CW by OH1TV
I received invitation to the 10th QRP Minimal Art Session from Lutz DL1RNN. QRPCC-club (http://www.qrpcc.de) is the organizer of the contest, where minimalistic QRP equipments shall be used. Max component count for a transmitter is 50. If there are less, bonus is given. The contest is on 80m CW.
http://www.kolumbus.fi/pekka.ketonen/4w%20single%20FET.htm

80 m Transceiver by GW4ALG
The home made transceiver covers 3.5 to 3.6 MHz and is CW only.
http://www.alg.myzen.co.uk/radio/qrp/80txr.htm

80 Meter CW Transceiver door PA2OHH
80 meter band CW transceiver met een directe conversie ontvanger met zijband onderdrukking.
http://www.qsl.net/pa2ohh/98txrxnl.htm
 

80 meter QRPp Radio by WA6OTP
This is a new Transmitter/Receiver for backpacking. This has a 800 milliwatt transmitter and an NE602 receiver. It now has side tone and a PTO RIT.
http://www.wa6otp.com/80.htm

80m FETer QRPp CW transceiver by G3XBM
Some years ago a beautifully simple circuit for a 40m CW transceiver by W2UW was published in GQRP SPRAT.
This inspired me to have a go at an even simpler version for 80m using just 14 parts apart from the key and crystal earpiece.
https://sites.google.com/site/g3xbmqrp3/hf/feter-80m-qrpp-cw-transceiver

80m XBM80-2 QRP CW transceiver by G3XBM
This is an experimental CW transceiver for 80m, although the same idea will work on all HF bands. So far I have only used it on the bench and not on the air. I have called it the XBM80-2 (80m two transistors - very original!).
https://sites.google.com/site/g3xbmqrp3/hf/80m_xbm80

An 80 Meter CW Five Watt QRP Transceiver by K3NG
This project originally started out on the bench as a 40 meter phone transceiver. Wanting to build a QRP with different capabilities than my other QRP rigs, I decided to go to 80 meters.
http://kambing.ui.ac.id/onnopurbo/orari-diklat/teknik/homebrew/80m-cw-k3ng/5%20Watt%2080%20Meter%20QRP%20CW%20Transceiver.htm

Eighty - Oner by SP5DDJ
For many Hams 80m band is most accesible, so I developed another one-watter based on VXO.
http://www.qsl.net/sp5ddj/eighty-oner.htm
 

KEROKERO - 80m transceiver CW QSK by PY2OHH
The 80m band is a bit deserted! We decided to build something, this is the first project in a series, it is a transceiver with simple parts, with a direct conversion receiver and a basic 4W TX.
https://www.qsl.net/py2ohh/trx/kerokero/kerokero.htm

Le transceiver QRP 80m de F6BCU by F6GLZ
Il se compose de plusieurs modules séparés, ce qui facilite leur mise au point. On trouve un module VFO, une partie réception suivie d’un amplificateur BF et le driver avec son P.A. pour la partie émission.
https://f6glz.wordpress.com/projets-en-cours/le-transceiver-qrp-80m-de-f6bcu/

MOHAIR ONE miniature 3.5 MHz CW transceiver by OH7SVhttp://www.saunalahti.fi/hohtola/mohair-one/

PIXIE 2 Transceiver G3LHJ's Version of WA6BOY's Tiny Rig
This modified version of W6BOY's little rig was published in Sprat number 88. The rig is designed for 80m and although very simple, it can give interesting results.
http://www.zerobeat.net/g3ycc/pixie2.htm

PUPS 80 by WA6OTP
Camp Radio
http://www.wa6otp.com/Pups80.html

The Micro-80 Mini Transceiver by RV3GM
The circuit is a simple QSK transceiver for 80 metres which could be adapted for other bands by changing the crystal and L,C in the output circuit.
http://www.qsl.net/g3pto/micro80.html

The RixPix by KE3IJ
Here's the schematic for my version, which I named the "RixPix", cuz it's, well, you know-- "Rick's Pixie"! At least it distinguishes my modified circuit from the others, should anyone out there actually want to try building it.
http://www.ke3ij.com/rixpix.htm

The ROSE 80 CW Transceiver by N1HFX
A great deal of interest has been generated by my previous design articles, so I decided to go to work on a full blown transceiver design. After several months of work, the ROSE-80 transceiver was born. This transceiver is similar to other designs but contains some unique differences.
http://www.rason.org/Projects/rose80/rose80.htm

Tiny Tornado for 80m by PA3HCM
Many years ago I built a prototype of the famous “Pixie 2”, one of the simplest and smallest CW transceivers ever designed. The main issue is that the TX and RX frequency is the same, so the opposite station needs to shift which he probably doesn’t know, so it takes quite some patience to get a successful QSO. Once published, lots of improved designs appeared in magazines and on the internet, one of them being the “Tiny Tornado”.
http://www.pa3hcm.nl/?p=1112

Unichip 80m CW Transceiver by GØUPL
This project somehow grabbed my imagination. It's a complete 80m transceiver in one chip, the CA3086 transistor array. One transistor for crystal oscillator, one for a PA, and three for the audio amplification ...
http://www.hanssummers.com/unichip.html