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 I am no expert builder by any means, cheap and cheerful. 
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Post I am no expert builder by any means, cheap and cheerful.
This may be ugly to some eyes as it has no fancy heat sink or a nice name embellished upon it but my cheap and cheerful dummy load should handle the output of my Trio S830S at around 100-150w all day long if needed, or at least those are my expectations.

Comprises of 20 of 1000Ω (1kΩ) 5% 5w carbon film resistors.
Two 25cm strips of LMR 400 centre conductor
One PL259 and a 3cm stub of LMR 400
Perfect 50Ω load over the multimeter.

Best of the all is the grand cost of £6 all in.


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John G Ritson CMH
Fri Aug 18, 2017 5:51 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
Nice. Stick it in a syrup tin full of oil.

Good work

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David. G4YVM


Fri Aug 18, 2017 5:53 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
I'd have made it circular... but hey, if it works!

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Paul


Fri Aug 18, 2017 6:58 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
G0TSG wrote:
I'd have made it circular... but hey, if it works!

It was meant to end up circular but took a mixed approach from multiple sides after reading so much online that the planning went out the window. ;)

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John G Ritson CMH


Fri Aug 18, 2017 7:16 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
whenever ive made them, ive done a circle - originally with 2 bits of pcb, then just used the resistor legs, with a brass rod (or 6mm copper cable) up the centre and into the connector.
I decided on this layout to eliminate any inductance, but i was probably over thinking it! lol

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Paul


Fri Aug 18, 2017 7:38 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
G0TSG wrote:
whenever I've made them, I've done a circle - originally with 2 bits of PCB, then just used the resistor legs, with a brass rod (or 6mm copper cable) up the centre and into the connector.
I decided on this layout to eliminate any inductance, but I was probably over thinking it! lol

I think there may be a little inductance or my meter on the tuner is out as it showed a 1.2.1 on the scale, but it gives me something to experiment with and gain a nice collection of RF burns along the way. :)

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John G Ritson CMH


Fri Aug 18, 2017 7:50 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
Nice! As someone else said... suspend in a can of oil, and it will handle much more.

It's something I could do with building actually. Every shack should have a high power dummy load.

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Fri Aug 18, 2017 8:25 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
...as for the 1.2 SWR... they're 5% tolerance resistors, so that may account for it.. maybe. 1.2 is fine though.


And also... you're realised the great thing about building your own stuff.... The cost :)

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Fri Aug 18, 2017 8:26 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
G0SLV wrote:
...as for the 1.2 SWR... they're 5% tolerance resistors, so that may account for it.. maybe. 1.2 is fine though.


And also... you've realised the great thing about building your own stuff.... The cost :)

I think I may get to like building my own stuff, but usually, I end up making a right mess of things and throwing the effigy into the bin afterwards.
Plus sourcing certain things become difficult at times. And yes 1.2 is more than fine for me as I think the MFJ tuner is probably out rather than my build using the 5% tolerance.

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John G Ritson CMH


Fri Aug 18, 2017 8:34 pm
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Post Re: I am no expert builder by any means, cheap and cheerful.
Keep at it. It's great aspect to the hobby, and you learn so much.


If you could see the first few things I built, you'll realise that your work is really quite neat :)

Each build gets better, and you learn the little touches that add refinement rather than functionality.


When you think about it.... this amp for the extension speaker I'm building at the moment will be shoved in a box and never seen again. I could have built it far easier on veroboard! I merely enjoy it. At the end of the day, it's what it works like that actually matters. Everything else is just show-boating.

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Fri Aug 18, 2017 8:57 pm
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 I am no expert builder by any means, cheap and cheerful. 
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Post Re: I am no expert builder by any means, cheap and cheerful.
G0SLV wrote:
Keep at it. It's a great aspect to the hobby, and you learn so much.


If you could see the first few things I built, you'll realise that your work is really quite neat :)

Each build gets better, and you learn the little touches that add refinement rather than functionality.


When you think about it.... this amp for the extension speaker I'm building at the moment will be shoved in a box and never seen again. I could have built it far easier on Veroboard! I merely enjoy it. At the end of the day, it's what it works like that actually matters. Everything else is just show-boating.

Yes, you could have done it much more haphazardly than what you chose but like yourself, I strive for perfection and I want my builds to come close or exceed that of the commercial offerings as in neat and organised. Within reason as some commercial offerings are well rough and almost ready not mentioning any names such as MFJ of course.
It could be the side of the hobby that keeps me interested as transmitting and talking is somewhat limited these days so much so I sold the Flex5000, beam, rotator and mast to go back to basics with a TS-830S as I can just about get my head around the workings of these TRX.

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John G Ritson CMH


Fri Aug 18, 2017 9:08 pm
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Post Re: I am no expert builder by any means, cheap and cheerful.
Addendum: Dummy load is perfect 1.1:1 as confirmed on a Daiwa meter it was the MFJ meter that is out at 1.2:1 which does not surprise me at all, after all, it is at best a visual guide and no more.

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John G Ritson CMH


Sat Aug 19, 2017 10:41 am
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Post Re: I am no expert builder by any means, cheap and cheerful.
A job well done then!

Excellent news.

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Sat Aug 19, 2017 12:11 pm
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