Can I convert my 20M QRP transmitter for audio transmission?

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SUMMARY

The discussion centers on converting a 20M QRP transmitter, specifically a Ramsey electronics kit, for audio transmission. The transmitter operates at 14 MHz and includes a crystal selector switch. Participants noted that converting the transmitter to AM is impractical due to its outdated use, while a rough FM modification may be possible by applying audio to the R1 control instead of the 12 volts. Additionally, the 27 MHz crystal mentioned is likely a 9 MHz 3rd overtone crystal, which would not function effectively for the intended purpose.

PREREQUISITES
  • Understanding of QRP radio operation
  • Familiarity with Ramsey electronics kits
  • Knowledge of AM and FM modulation techniques
  • Basic concepts of crystal oscillators and frequency bands
NEXT STEPS
  • Research modifications for Ramsey electronics kits
  • Learn about AM and FM modulation techniques in radio transmission
  • Explore the functionality of crystal oscillators, particularly 3rd overtone crystals
  • Join a local radio club to gain hands-on experience and knowledge
USEFUL FOR

Amateur radio enthusiasts, electronics hobbyists, and individuals interested in radio transmission modifications will benefit from this discussion.

robotnut
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Hello all;

Wifey got me a 20M QRP radio transmitter (1watt) for X-mas, knowing I love playing with this stuff:-p

I have never heard of QRP before and was very surprised to find that there is no audio input on it:bugeye:

So I stuck the kit together in about 2 hours and my spectrum analyzer has me convinced it is working on the assigned freq. It is a Ramsey electronics kit.
This kit comes with 2 crystal sockets and a crystal on the 14mhz band and a crystal selector switch.
The question:

What would it take to convert or mod this for audio transmission? My 2nd crystal is on the 27MHZ band for CB. I want to so it because it would a fun learning experience and I already have a 27mhz receiver.
 

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That was a sweet present, but you must not attach an antenna to it and transmit if you don't have a Ham licence.

Your 27 MHz crystal is probably really a 9 MHz 3rd overtone crystal, so it is unlikely to work on 27 MHz in this circuit although you may hear a 3rd harmonic. Any radiated power would be mostly at 9 MHz.

If you have such an interest, why not visit a local radio club and meet some Hams? Maybe there is a course you could join to learn more about Radio and Electronics?

It is probably not realistic to convert this transmitter to AM as AM is not really used any more and it would also be quite a serious modification.
Some FM might be possible if you put audio on the R1 control instead of the 12 volts, but it would probably be pretty rough.
 

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