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#1
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Hi Group,
My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I have a few CBs around that I could use the RF amp to get me on 10 meter but I am not sure of the drive level. I am not sure if this amp would work below 24 MHz without re-tuning. Anyone have a simple wideband circuit that could cover 3.5 to 28 MHz? de KJ4UO |
#3
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In article ,
says... Hi Group, My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. This is not something I would recommend. While the theory is that good RF test equipment should have better spectral purity, and lack of harmonics, than the radio gear it's testing, my experiences with Wavetek along these lines have not been good. Anyone have a simple wideband circuit that could cover 3.5 to 28 MHz? My gut reaction is that "Simple" and "Wideband" do not go together in this context as far as a clean signal is concerned. Suggest examining the 'Radio Amateur's Handbook' and 'RF Design for the Radio Amateur' (I think that's the title) for design considerations. I still think that, if you want to just do a simple QRP CW transmitter, you'd be better off going with one of the existing designs in one of those two books (or similar such pubs). -- Dr. Anton Squeegee, Director, Dutch Surrealist Plumbing Institute (Known to some as Bruce Lane, KC7GR) kyrrin a/t bluefeathertech d-o=t c&o&m Motorola Radio Programming & Service Available - http://www.bluefeathertech.com/rf.html "Quando Omni Flunkus Moritati" (Red Green) |
#4
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My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I
need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I did something similar when I first was licenced in 2001, but I would not recommend it now. I used my Leader LSG-216 signal generator as a VFO followed by a 1 Watt amplifier that I put together myself. It worked and I had several QSO's with it, but after several RST xx8 reports I found that the signal generator had hum modulation and some jitter. I have later learnt that this is almost inherent in a synthesizer which covers a large frequency range. It has very large VCO gain: MHz/Volts - change in frequency per change in voltage in order to cover the large frequency range. But this also makes it very sensitive to noise in the control voltage. As a signal generator, i.e. a tool for aligning circuits and so on, this is not a problem. Sverre LA3ZA www.qsl.net/la3za |
#5
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My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I
need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I did something similar when I first was licenced in 2001, but I would not recommend it now. I used my Leader LSG-216 signal generator as a VFO followed by a 1 Watt amplifier that I put together myself. It worked and I had several QSO's with it, but after several RST xx8 reports I found that the signal generator had hum modulation and some jitter. I have later learnt that this is almost inherent in a synthesizer which covers a large frequency range. It has very large VCO gain: MHz/Volts - change in frequency per change in voltage in order to cover the large frequency range. But this also makes it very sensitive to noise in the control voltage. As a signal generator, i.e. a tool for aligning circuits and so on, this is not a problem. Sverre LA3ZA www.qsl.net/la3za |
#6
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"Sverre Holm" wrote in message
... My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I did something similar when I first was licenced in 2001, but I would not recommend it now. I used my Leader LSG-216 signal generator as a VFO followed by a 1 Watt amplifier that I put together myself. It worked and I had several QSO's with it, but after several RST xx8 reports I found that the signal generator had hum modulation and some jitter. I have later learnt that this is almost inherent in a synthesizer which covers a large frequency range. It has very large VCO gain: MHz/Volts - change in frequency per change in voltage in order to cover the large frequency range. But this also makes it very sensitive to noise in the control voltage. As a signal generator, i.e. a tool for aligning circuits and so on, this is not a problem. Sverre LA3ZA www.qsl.net/la3za One must wonder about another "possible" problem as well. If even a fraction of transmitted RF were to get back into the sig gen, it may upset the balance as well causing any sort of problems. Much like when RF gets back into a Power Supply situated close by - creates hum and so on - on the signal. Some Sig Gens may not have enough shielding to protect from this. Their shielding may very well prevent signals from leaking OUT when testing from it's own source, but not designed to fight off Transmitted RF getting back into it. I'm not saying those things WILL happen, but certainly possible. Otherwise, the idea is interesting and I'm sure many others unmentioned have thought of or have actually tried it. I being one. On another note along these lines, though I didn't see it or hear it, I heard a ham on 2 meters once who claimed to take a Bearcat scanner - a 250 model I believe.. and used it in much the same manner... I'd love to have seen and heard it up close. G.W. |
#7
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"Sverre Holm" wrote in message
... My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I did something similar when I first was licenced in 2001, but I would not recommend it now. I used my Leader LSG-216 signal generator as a VFO followed by a 1 Watt amplifier that I put together myself. It worked and I had several QSO's with it, but after several RST xx8 reports I found that the signal generator had hum modulation and some jitter. I have later learnt that this is almost inherent in a synthesizer which covers a large frequency range. It has very large VCO gain: MHz/Volts - change in frequency per change in voltage in order to cover the large frequency range. But this also makes it very sensitive to noise in the control voltage. As a signal generator, i.e. a tool for aligning circuits and so on, this is not a problem. Sverre LA3ZA www.qsl.net/la3za One must wonder about another "possible" problem as well. If even a fraction of transmitted RF were to get back into the sig gen, it may upset the balance as well causing any sort of problems. Much like when RF gets back into a Power Supply situated close by - creates hum and so on - on the signal. Some Sig Gens may not have enough shielding to protect from this. Their shielding may very well prevent signals from leaking OUT when testing from it's own source, but not designed to fight off Transmitted RF getting back into it. I'm not saying those things WILL happen, but certainly possible. Otherwise, the idea is interesting and I'm sure many others unmentioned have thought of or have actually tried it. I being one. On another note along these lines, though I didn't see it or hear it, I heard a ham on 2 meters once who claimed to take a Bearcat scanner - a 250 model I believe.. and used it in much the same manner... I'd love to have seen and heard it up close. G.W. |
#8
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I thought the Leader Sig Gens were free running and not very stable. Maybe
it is a new model. If you simply want a CW TX, why not build the VFO as well? There are plenty of designs around. If you do want to use the RF gen , you could always follow it with a low pass filter. Richard Sverre Holm wrote in message ... My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I did something similar when I first was licenced in 2001, but I would not recommend it now. I used my Leader LSG-216 signal generator as a VFO followed by a 1 Watt amplifier that I put together myself. It worked and I had several QSO's with it, but after several RST xx8 reports I found that the signal generator had hum modulation and some jitter. I have later learnt that this is almost inherent in a synthesizer which covers a large frequency range. It has very large VCO gain: MHz/Volts - change in frequency per change in voltage in order to cover the large frequency range. But this also makes it very sensitive to noise in the control voltage. As a signal generator, i.e. a tool for aligning circuits and so on, this is not a problem. Sverre LA3ZA www.qsl.net/la3za |
#9
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I thought the Leader Sig Gens were free running and not very stable. Maybe
it is a new model. If you simply want a CW TX, why not build the VFO as well? There are plenty of designs around. If you do want to use the RF gen , you could always follow it with a low pass filter. Richard Sverre Holm wrote in message ... My wavetek sig gen covers 100KHz to 512 MHz and puts out about 10mW. I need a simple circuit to cover HF which will boost this up to 500mW. I would like to try out the signal generator as a low power CW transmitter. I did something similar when I first was licenced in 2001, but I would not recommend it now. I used my Leader LSG-216 signal generator as a VFO followed by a 1 Watt amplifier that I put together myself. It worked and I had several QSO's with it, but after several RST xx8 reports I found that the signal generator had hum modulation and some jitter. I have later learnt that this is almost inherent in a synthesizer which covers a large frequency range. It has very large VCO gain: MHz/Volts - change in frequency per change in voltage in order to cover the large frequency range. But this also makes it very sensitive to noise in the control voltage. As a signal generator, i.e. a tool for aligning circuits and so on, this is not a problem. Sverre LA3ZA www.qsl.net/la3za |
#10
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