Author Topic: A newbie question about a transmitter  (Read 241 times)

CharlieFoxtrot

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A newbie question about a transmitter
« on: April 26, 2018, 2007 UTC »
Hello everyone! CF here! As the title says, iīm new on circuit building, but trying to do someting. Iīve been thinking about building the Grenade, to start a PRadio now that iīm living in the countryside, but havenīt seen enough examples to know if the schematics i found online (see below) are working or not. There are at least 3 or 4 different variations, but no examples. So, is it something you can recommend to start? Could i have a happy ending trying to build it? Is there any other transmitter you could give me advice with about 10w?

Thanks in advance.
CF

http://worldwidedirt.tripod.com/gproject.html vs http://am-transmitter.blogspot.cl/2014/07/grenade-transmitter.html

Stretchyman

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Re: A newbie question about a transmitter
« Reply #1 on: April 26, 2018, 2145 UTC »
Stick withe the LuLu design, I can send you a PCB if you want?

Str.
'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


                                              ;)

redhat

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Re: A newbie question about a transmitter
« Reply #2 on: April 27, 2018, 0003 UTC »
I agree.  As a beginner, its a lot easier to start with something that works, learn how it works, then build your own.  Thats what I did many moons ago.

+-RH
Somewhere under the stars...
WinRadio Excalibur/305 w/ a chi-town resonant loop, Kenwood KDC-U356 for mobile listening.
Please send QSL's and reception reports to xfmshortwave [at] gmail [d0t] com

CharlieFoxtrot

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Re: A newbie question about a transmitter
« Reply #3 on: April 27, 2018, 1135 UTC »
Stick withe the LuLu design, I can send you a PCB if you want?

Str.

PMd

CharlieFoxtrot

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Re: A newbie question about a transmitter
« Reply #4 on: April 27, 2018, 1155 UTC »
Itīs impossible not to think about the LULU. It sure itīs a great TX. Believe me, itīs been in my sight for a long time already. Thnk you both.

CF

Stretchyman

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Re: A newbie question about a transmitter
« Reply #5 on: April 30, 2018, 1944 UTC »
Single ended class E is as simple (and efficient) as it gets.

I've heard folk say it was complex when it's actually simpler than most other modes of RF generation as it doesn't need bias for a start.

Using the 74HC240 and an IRL510 (IRF510 wont work BTW despite lots of designs say it does, IT DOESN'T!) your're good to 8MHz or so.

Ive seen the cap across the FET specified as 68p which must have been a typo as 680 is nearer the mark, I use 470p as you can use them for all the O/P caps (1n5 = 3x470)

COG/NPO caps are essential, you can however get away with X7R for the coupling cap, HV COG's at this value are VERY expensive!

Also using T50-2 toroids is stoopid as they're way too small and get roasting hot, T80-2 abs min, T94-2 perfect and T106's for the 40W GaN version.

So this is the ONLY design to use (it's not mine BTW!), every other is pants, overly complex, doesn't work, uses way too many unobtainable components etc etc.

Also having a broadband driver makes it work on any freq, just change the 7 components to RHS of FET.

Str.
« Last Edit: April 30, 2018, 2005 UTC by Stretchyman »
'It's better to give than receive' so why RX when you can TX!

                            Buy one from me, NOW!

Great discounts on ALL my transmitters if purchased via HFUnderground


                                              ;)