Anyone know how to build this kit (making the inductors), and tuning it?
I have a kit of all parts, but the seller does not reply for further details

 

Does the kit contain the ferrite beads that appear asT1, T2, and T3??? Is there a picture of the completed linear amplifier?? What frequency range is it intended for?? What power output is it claimed to deliver??There are quite a few published plans for linear and class "C" amplifiers published.

The amplifier may be one where the original plans were published in one of the main ham radio magazines.
WHERE did you see the a for the kit?? and what is the name of the organization you bought it from??
ALSO, will you please let us know what that text in the drawing title block reads.

 

What frequency range is it intended for??

The schematic shows "input -10 dBm @ 3 - 30 Mhz" .

There would be a licence needed to operate the amplifier.

Bertus

 

A schematic that is in focus would be nice...

 

I did not realize that this is an illegal device, so Im parting ways with it. I was asked to help someone to build this, but not if its illegal

 

Actually, the license and regulations only apply if there is any signal radiated.
As I study the posted circuit more closely, it is less clear as to if the amplifier would actually work..
AND, it is not apparent that the assembly has any actual adjustment points at all, except for adjustable gate bias for the output devices. I see no adjustable capacitors or inductors.
I am guessing that T1, T2, and T3 are some type of transmission line transformers wound on some kind of ferrite beads, although certainly with no apparent construction information there is no assurance that they will work over the claimed frequency range.

 

Cannot read well the details; perhaps you can. Should be about the same :
----> https://vu3wjm.blogspot.com/2017/01/x-irf510-rf-amplifier.html
----> https://f5npv.wordpress.com/irf530-mosfet-amplifier/
----> https://rowaves.com/25w-hf-linear-amplifier-2-x-irf510-miudihno-py2ohh/
And the IRF510 can have application notes to check.

It is not illegal to build; those obsolete regulations are for U.S.A.

 

It is NOT illegal to own or build it. It is, however, illegal to use it to broadcast a signal on a frequency that you are not licensed to operate on. You can legally output a signal into a dummy load as long as it stays within the dummy load.

 

i Finally received info on building this from the designer, but to be honest EVERYTHING is so questionable I may just send it back to my friend. In the info package, there is much trace cutting on the PCB and weird coil winding. Im just too busy for this, especially when I see wired and tested boards on EBay for only $10.00 more than the kit.

 

china has gotten further into the RF business. The Baofeng handi talkie is but only 1 example. Yes, it does transmit. But (and it's a big but) they are illegal to use on the GMRS bands because their transmit signal is filled with harmonics that splatter all over the adjacent channels. I looked at what was available from china recently when shopping for a 2M/70cm mobile rig. I couldn't bring myself to buy one for many reasons. I was in a pinch to replace an end-fed antenna that was trashed by a large limb falling into it ripping the balun apart and tangling the wire. Amazon had a nice 10/15/20/40/80M end-fed antenna with an 80M trap. So, I went to the effort of hanging it and tried to use it. First using my XCVR's auto antenna tuner and then an additional external auto antenna tuner. NO GO! So, I put the NanoVNA on it and swept the 3 to 55MHz band checking for SWR dips. The dang antenna's SWR was >20 across the board. Completely maxed out and no dips at all. So, I checked a narrow sweep of just the XMT frequencies ranges for each operating band and was getting 26 SWR or higher. The antenna's balun was a complete piece of junk (I suspect it wasn't even a balun and was completely empty). I was already suspicious of it as there was no lug for the counter-poise/ground connection. The antenna was ~100USD which is typical for the type of antenna but a 103' piece of wire for 100USD is a bit much. Nope, I'll leave the chinese RF stuff alone until someone starts giving reliable good reviews on it.

 

china has gotten further into the RF business. The Baofeng handi talkie is but only 1 example. Yes, it does transmit. But (and it's a big but) they are illegal to use on the GMRS bands because their transmit signal if filled with harmonics that splatter all over the adjacent channels. I looked at what was available from china recently when shopping for a 2M/70cm mobile rig. I couldn't bring myself to buy one for many reasons. I was in a pinch to replace an end-fed antenna that was trashed by a large limb falling into it ripping the balun apart and tangling the wire. Amazon had a nice 10/15/20/40/80M end-fed antenna with an 80M trap. So, I went to the effort of hanging it and tried to use it. First using my XCVR's auto antenna tuner and then an additional external auto antenna tuner. NO GO! So I put the NanoVNA on it and swept the 3 to 55MHz band checking for SWR dips. The dang antenna's SWR was >20 across the board. Completely maxed out and no dips at all. So, I checked a narrow sweep of just the XMT frequencies for each operating band and was getting 26 SWR or higher. The antenna's balun was a complete piece of junk. I was already suspicious of it as there was no lug for the counter-poise/ground connection. The antenna was ~100USD which is typical for the type of antenna but a 103' piece of wire for 100USD is a bit much. Nope, I'll leave the chinese RF stuff alone until someone starts giving reliable good reviews on it.

Thats the other problem for me I dont have the skills, knowledge or equipment to make certain this doesnt splatter all over the place

 

There are LTSpice simulations of wideband RF amplifiers.
In those simulations it is possible to understand the cause and effect by modifying component values.
The requirements for a Technician license is not too difficult to pass
HamExam.org: Free Amateur Radio Practice Tests with Flash Cards

Regarding splatter, we almost always need a low pass filter but wide band arrangements are even more complex.
An ATU automatic antenna tuner can be used to facilitate matching between wide band RF amp and antenna.
The S11 characteristics over wide band can have multiple peaks. This multiplicity can be so arranged
improving the selected band and attenuating between. Wideband is more complex involving more matching
than a fixed frequency, The ability to move between bands without laborious adjustments each time is useful.

 

There are LTSpice simulations of wideband RF amplifiers.
In those simulations it is possible to understand the cause and effect by modifying component values.
The requirements for a Technician license is not too difficult to pass
HamExam.org: Free Amateur Radio Practice Tests with Flash Cards

For any simulations to be even slightly close to accurate you need accurate component values, including the transformers. Given the lack of information, that may be a serious challenge.

 

There are LTSpice simulations of wideband RF amplifiers.
In those simulations it is possible to understand the cause and effect by modifying component values.
The requirements for a Technician license is not too difficult to pass
HamExam.org: Free Amateur Radio Practice Tests with Flash Cards

Regarding splatter, we almost always need a low pass filter but wide band arrangements are even more complex.
An ATU automatic antenna tuner can be used to facilitate matching between wide band RF amp and antenna.
The S11 characteristics over wide band can have multiple peaks. This multiplicity can be so arranged
improving the selected band and attenuating between. Wideband is more complex involving more matching
than a fixed frequency, The ability to move between bands without laborious adjustments each time is useful.

egads!!!!..THATS WHY IM NOT TOUCHING THIS!!

 

The present technician test covers rules and regulations and procedures. Stuff that needs to be memorized. I don't recall anything technical except maximum transmitter power.
We still do not have any hint about what frequency or how much power. OR what sort of purpose.

 

It covers a wide frequency, but I just found out that it primarily seems to be used with CB Radio, which is DEGFINATELY illegal, and therefore Im not touching it

 

It covers a wide frequency, but I just found out that it primarily seems to be used with CB Radio, which is DEGFINATELY illegal, and therefore Im not touching it

Given the quality of the drawing that was what I suspected. The circuit will probably be legal to use for Licensed Amateur Radio use, but it may need additional filtering of the output. WHAT was your intended applicatio for the amplifier??