HFU HF Underground
Technical Topics => The RF Workbench => Topic started by: partee on September 07, 2022, 0826 UTC
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Hi everyone,
I'm new to RF and electronics in general. I'm want to build a Fireball transmitter as described in the 11/90 issue of 73 magazine. One of the parts is a relay from Radio Shack (RS 275-243). It's no longer sold. Does anyone know of a replacement? Thanks for any help.
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Is this it?
https://www.ebay.com/itm/324063572076
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Any 5V relay would work. I wonder what you intend to do with it?
Str.
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Is this it?
https://www.ebay.com/itm/324063572076
yes
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Any 5V relay would work. I wonder what you intend to do with it?
Str.
I want to make a Fireball transmitter
https://imgur.com/a/vbvoDvB (https://imgur.com/a/vbvoDvB)
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What do you intend to do with the transmitter?
Oh, it doesn't look much if a fireball at all.
I guess it is tongue in cheek!
I don't get it?
Turn an oscillator on and off?
Is that it??
Str
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Oh, it doesn't look much if a fireball at all.
We can fix that.
If he runs enough RF power to burn or weld the relay contacts and then hot switches the relay, then he might just be able to make an actual fireball. (This would require quite a bit more RF power than the 40 milliWatts listed on the schematic.)
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Yes, I'm concerned the author is under the impression the circuit will offer any meaningful function.
The first radio circuit I ever made was a spark gap transmitter, that worked very well and transmitted on every frequency!
Str.
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`73 once published a detailed schematic of a spark gap transmitter. At the end of the article there was a warning you didn't want to put it on the air. They had another interesting one when fluorescent light bulbs hit the market and they found out the things oscillated at lower end of 80 meters. A complete schematic for a QRP CW rig using one, with the warning "for experienced operators only" at the end. You had to love Wayne Green.
However, the propagation charts by Tomas Hood were dead on.
Anyone want to buy some colloidal silver?
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The Fireball, if my memory isn't completely gone, was a QRP CW rig from the 1990's. There were kits for sale and variations on it. It was along the lines of the "Pixie" and the "Talking Pixie". Now behave yourselves or I'll have to set Fansome's ghost loose on you.