Compatibilty problems with 300w amp & LPF?

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teckniqs
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Re: Compatibilty problems with 300w amp & LPF?

Post by teckniqs » Tue May 03, 2016 8:18 am

A dummyload is a 50 ohm load and is fine without the cap, it's the colinear antenna you need to watch.

nrg-uk
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Re: Compatibilty problems with 300w amp & LPF?

Post by nrg-uk » Tue May 03, 2016 9:38 am

I was just going by what broadcast concept said on there website about the LPF
https://broadcastconcepts.com/150W-FM-LPF.html

Elopid
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Re: Compatibilty problems with 300w amp & LPF?

Post by Elopid » Thu May 05, 2016 9:40 am

nrg-uk wrote:I was just going by what broadcast concept said on there website about the LPF
https://broadcastconcepts.com/150W-FM-LPF.html
Good morning nrg-uk,

Gosh I had no idea that these LPF were only rated at 150w continuous and are just marked at 500w short term peak like a Chinese Hi-Fi PMPO!
Thankfully I never purchased them and I think that's a joke how they mark them up as 500w but sell them as a 150w unit.
I have a Dutch RF Shop 300w amplifier which has the exact same SMT caps as this 150w LPF but the coils are thinner on the LPF. Do you think I should upgrade the coils to a thicker SWG or change the caps?

I appreciate you pointing this out, cheers ELo

Elopid
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Re: Compatibilty problems with 300w amp & LPF?

Post by Elopid » Thu May 05, 2016 9:48 am

Analyser wrote:Just to add my 2p into this thread again. The low pass filter in the pictures is fine, even for 500w. If you put too much power in to a filter either the coils get really hot or the capacitors explode, it won't cause a mismatch within a few seconds and blow the PA.
Broadcast concepts stuff is quite good but looking at the pictures of the Spanish stuff I'm not that impressed.
Cheers Analyser,

I am a bit concerned with it being only rated at 150w continuous and with Broadcast Concepts featuring a high powered version which is still only rated at 250w. But as I previously said to the last poster I have another (300w) amp with the same capacitors on it.
When I get around to it I will replace the two transistors for another matched pair, in the meantime I'll be working on further projects and come back to this at a later date.
I highly appreciate all your help, I'm sure it won't be long until I'm back again.

With thanks, eLopiD

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rigmo
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Re: Compatibilty problems with 300w amp & LPF?

Post by rigmo » Tue Feb 02, 2021 4:52 pm

nrg-uk wrote: Thu Apr 28, 2016 4:26 pm That low pass filter is only rated for 150 watts
Tru for LPF, 1.2mm wire support 300w... 2.9mm support 1kw

Chris why you not replay me I still wait you. do you ok ? what is problem ?

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