The Larkspur C11  transmitter

I bought one 30 years ago intending it to give me incentive to learn Morse.  I still havent learned morse, but I still have the C11 and now I dont have to learn morse ! Cool!  It is primarily a CW unit but will do AM (phone)  MCW and FSK. Covers 2Mhz to 16Mhz ( completely misses 160M )

Uses hi stability master oscillator which is multiplied for the higher bands. The master oscillator module is a masterpiece of precision mechnical engineering. All I have is excepts from the manual, but they are schematics!

The usual advice applies, the full EMER is available from , their manual is complete and the quality is superior.

These images are links to high resolution images

page 4page 3page 2

page 6page no unknownpage 8

page 7 (?)page 11page 9 (maybe)

relays and filamentsmic amp, amc, CW  sidetoneAM modulator and amc

audio chain, amc and AM modulatorbuffer amp, harmonic multipliers and RF power amp

external rotary transformer unitmore of the schematicmore of the schematic

Copious apologies for the quality, but they have gone through many generations of copies of copies of copies of copies and my "originals" have been yellowing away for the last thirty years.

This was the transmitter portion of a radio transmitter combination. I believe the compansion radio equipment was called an R210, I remember looking at one in the disposals shop when I was 15 and feeling sad that I would never have enough pocket money to buy it back then.  People tell me that the radio was pure gold, so solid that it could be pushed of the bench and fall on to concrete and the beat note would not change. I dont doubt it.  I still dont have an R210.  Old hams I meet tell me "...ahhh I used tah have one of them...threw it away years ago...didnt have a product detecter...useless !! ahhh... " and so on.  There were for a while C11 sets going for a song in Melbourne from army disposal vendors. I bought mine in 1978 for ten dollars.  I do not have the rotary transformer power supply unit and I have not had time to biuld a PSU for this transmitter yet.  If you go to Seaworld in Queensland there is the power unit on display as a prop in the Burmuda Triangle Ride. Its meant to look like a mysterious piece of WW2 technical paraphernalia....kind of breaks the magic if you know what the prop actually is!

Here is some images of the C11 interior.  They dont biuld them like this anymore! Needless to say the biuld quality is impeccable, true of all the Larkspur radios that I have seen. 

elaborate clockwork for tuninggreen box is the VFO, turbine for coolingno seperate final tuning, its all geared and cammed to be RIGHT
vfo and AM plate modulation transformer,below 100KCS crystal harmonic generator,middle MO boxRF power amplifier
output tuning and PA bottlesprecision clockwork for tuning

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 Wed Apr 16 18:48:32 EST 2008 to improve web useability, added images