3.5MHz ARDF Transmitter by ON7YD
This transmitter is designed as a classic 3 stage TX.
http://www.qsl.net/on7yd/atx80.htm
 

3.5MHz Low PowercARDF Transmitter by ON7YD
This low power transmitter is developed for ARDF exercising purposes but of course can be used as super QRP transmitter either.
http://www.qsl.net/on7yd/minitx80.htm

80-meter CW Transmitter by K9PPW
This is a schematic of Bob's homebrew QRP transmitter. It's CW on 80 meters, about 1 watt output, VFO ... and only uses TWO rf transistors and one more for keying. It was built as an experiment to see what you could get out of ONE transistor (about 250 mw with no chirp) and the "shoes" were added later to get a whopping one watt of rf out.
http://my.core.com/~jematz/qrp/k9ppw-s1.htm

80/40 meter CW transmitter with 6BM8/ECL82 by SM5GNN
This is my own variation of the triode/pentode family of glowbug transmitters. It features a Pierce oscillator which runs continously during transmit to avoid chirp.
http://www.algonet.se/~janax/ecl82bug.htm

Fuchsjagdsender - Der kleine Fox durch DL1DMW
Wer schon einmal an einer Fuchsjagd teilgenommen hat, weiß, wie viel Spaß sie bereiten kann. Für die Fuchsjagden des Ortsvereins Soest, wurde dieser wenig aufwendige 80-m-Fuchs aus zwei vorhandenen Lösungen kombiniert.
http://www.amateurfunkbasteln.de/fox/fox.html

My One and Two Valve Transmitters for 80mtrs by G4KKI
Presented is a double sideband transceiver that Dick calls "Wee Willy". This rig has a low parts count and is easily built using non-etched PC board techniques.
http://homepage.ntlworld.com/g4kki.bill/one_valve_transmitter_for_80mtrs1.htm

OARC-80 by WAØITP
This is a fun little QRP transmitter that was developed for a club project. I had wanted to try an oscillator on a chip, but had heard the Epson chips had phase shift problems.
http://www.wa0dx.org/wa0itp/oarc80.html

Simpel betrouwbaar 3Watt 3,6MHz ARDF/QRP zendertje door PAØNHC
Dit is een eenvoudig 2-traps zendertje, dat door de uitgekiende oscillatorschakeling (uit Solid State Design) een mooi CW toontje geeft.
http://www.xs4all.nl/~nhcjv/ardf/tx80/tx80.htm

Simple 80m TX by EI9GQ
This simple circuit will give about 1.2 Watts of output when powered from a 13.8VDC supply. If you don't have a 2SC1237, try any other 12V CB radio output transistor 2SC1969, 2SC1307 etc.
http://www.zerobeat.net/g3ycc/ei9gq.htm

TAG 80 Transmitter by G4RAW
Original Circuit in SPRAT Summer 1994 Iss Nr 79
The original version was built on tag strip, hence the name.
http://www.qsl.net/g3pto/g4raw.html

Ten Minute Transmitter by G4RAW
Steve, G4RAW described this simple transmitter for 80 metres in Sprat 82 and describes how the World record for building a rig , actually a Oner, and having a QSO, is under 15 minutes.
http://www.zerobeat.net/g3ycc/tenmin.htm

The Nipper 3.5MHz Transmitter
I think that this circuit was developed by G3ROO but my notes are lacking in this information.
http://www.qsl.net/g3pto/nipper.html