EFHW 80M Loading coil
- Buick Mackane
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EFHW 80M Loading coil
Anybody ever tried adding an 80m loading coil to a 40m EFHW ? If so what was your bandwidth on 80m & VSWR ?
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Re: EFHW 80M Loading coil
SWR is no problem you just get a very narrow band width can't remember what but narrow.
- Buick Mackane
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Re: EFHW 80M Loading coil
Ok alan thanks for replying
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- Buick Mackane
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Re: EFHW 80M Loading coil
There's a guy selling these coils on ebay for £25, I'll knock one up for a fraction of that price (£5 for magnet wire) i'll report back with my findings
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Re: EFHW 80M Loading coil
Just need about a 110uH coil and about 2m of rat tail after it, I get 80m on mine using this. The bandwidth is narrow but the band edges do come in using the built in radio ATU.
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Re: EFHW 80M Loading coil
What bandwidth do you get without the ATU ?securityguy wrote: ↑21 Apr 2023, 13:43 Just need about a 110uH coil and about 2m of rat tail after it, I get 80m on mine using this. The bandwidth is narrow but the band edges do come in using the built in radio ATU.
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- Whisky1
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Re: EFHW 80M Loading coil
I got about 500khz usable spread before I needed a tuner, 49/1 with around 60ft of wire then 110 with a tail of around 6 feet.
I was ok with it for the size and whilst it wasn't a dx buster I did work s/america and india on 100 watts at around 40ft L config no radials.
I was ok with it for the size and whilst it wasn't a dx buster I did work s/america and india on 100 watts at around 40ft L config no radials.
- Buick Mackane
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Re: EFHW 80M Loading coil
Nothing wrong with 500 khz bandwidth, That's more than the entire 80m band, Suppose it depends on a few factors like height above ground etcWhisky1 wrote: ↑21 Apr 2023, 15:24 I got about 500khz usable spread before I needed a tuner, 49/1 with around 60ft of wire then 110 with a tail of around 6 feet.
I was ok with it for the size and whilst it wasn't a dx buster I did work s/america and india on 100 watts at around 40ft L config no radials.
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Re: EFHW 80M Loading coil
Mine is tuned perfectly on 3674khz and goes to 2:1 at 3743khz and 3632khz so almost 100khz is 2:1 or better.Buick Mackane wrote: ↑21 Apr 2023, 14:02What bandwidth do you get without the ATU ?securityguy wrote: ↑21 Apr 2023, 13:43 Just need about a 110uH coil and about 2m of rat tail after it, I get 80m on mine using this. The bandwidth is narrow but the band edges do come in using the built in radio ATU.
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Re: EFHW 80M Loading coil
I'd be happy with thatsecurityguy wrote: ↑21 Apr 2023, 17:42Mine is tuned perfectly on 3674khz and goes to 2:1 at 3743khz and 3632khz so almost 100khz is 2:1 or better.Buick Mackane wrote: ↑21 Apr 2023, 14:02What bandwidth do you get without the ATU ?securityguy wrote: ↑21 Apr 2023, 13:43 Just need about a 110uH coil and about 2m of rat tail after it, I get 80m on mine using this. The bandwidth is narrow but the band edges do come in using the built in radio ATU.
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Re: EFHW 80M Loading coil
Let us know how you get on. If you're making your own coil, this is the best calculator imo because it allows you to put your target henries value in and spits out the required dimensions based on what you have https://www.translatorscafe.com/unit-co ... inductanceBuick Mackane wrote: ↑21 Apr 2023, 18:39I'd be happy with thatsecurityguy wrote: ↑21 Apr 2023, 17:42Mine is tuned perfectly on 3674khz and goes to 2:1 at 3743khz and 3632khz so almost 100khz is 2:1 or better.
- Buick Mackane
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Re: EFHW 80M Loading coil
Cheers for that, Reckon i'll need around 80 turns of 0.63mm wire on a 42mm OD Former, I'll post the results when i get it set upsecurityguy wrote: ↑21 Apr 2023, 19:04Let us know how you get on. If you're making your own coil, this is the best calculator imo because it allows you to put your target henries value in and spits out the required dimensions based on what you have https://www.translatorscafe.com/unit-co ... inductanceBuick Mackane wrote: ↑21 Apr 2023, 18:39I'd be happy with thatsecurityguy wrote: ↑21 Apr 2023, 17:42
Mine is tuned perfectly on 3674khz and goes to 2:1 at 3743khz and 3632khz so almost 100khz is 2:1 or better.
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- Buick Mackane
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Re: EFHW 80M Loading coil
Did adding the 80m trap effect the SWR on the other bands ?
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Re: EFHW 80M Loading coil
It's not supposed to, but in reality it did a bit, but nothing significant.Buick Mackane wrote: ↑21 Apr 2023, 19:20 Did adding the 80m trap effect the SWR on the other bands ?
- Buick Mackane
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Re: EFHW 80M Loading coil
securityguy wrote: ↑21 Apr 2023, 19:28It's not supposed to, but in reality it did a bit, but nothing significant.Buick Mackane wrote: ↑21 Apr 2023, 19:20 Did adding the 80m trap effect the SWR on the other bands ?
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