Date: Wed, 26 Dec 2018 23:26:48 +0100 (CET)
From: Jacek Lipkowski <sq5bpf@lipkowski.org>
To: rsgb_lf_group@blacksheep.org
In-Reply-To: <alpine.DEB.2.11.1812262302011.1809@mailn.lipkowski.org>
Message-ID: <alpine.DEB.2.11.1812262317080.1809@mailn.lipkowski.org>
References: <CF6820823EF84DF6BFF1C4EFAE7A675D@Clemens0811> <5C23CB7D.2050306@posteo.de> <alpine.DEB.2.11.1812262302011.1809@mailn.lipkowski.org>
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Subject: Re: LF: VU2BGS
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iI forgot, old TV flyback transformers are also useful as a source of 
ferrite for power applications.

Also the HV windings on these transformers (at least from TVs made in 
Poland) have 1-1.5H inductance. This gives a nice resonance at 8kHz with a 
40m longwire. Useful for receiving VLF (i've received one of Stefan's 
first transmissions using this antenna), and also for transmitting (i can 
receive my signal in QRSS60 at 1.2km) from my antenna.

You can also use the transformers from old PC power supplies. They work 
well at 136 and 472kHz.

I'm sure you will find other sources of ferrite when you look around. 
There is plenty of junk that can be recycled into useful amateur radio 
components. Not everything has to be bought at Mouser.

VY 73

Jacek / SQ5BPF


On Wed, 26 Dec 2018, Jacek Lipkowski wrote:

> Date: Wed, 26 Dec 2018 23:11:11 +0100 (CET)
> From: Jacek Lipkowski <sq5bpf@lipkowski.org>
> Reply-To: rsgb_lf_group@blacksheep.org
> To: rsgb_lf_group@blacksheep.org
> Subject: Re: LF: VU2BGS
> 
> Instead of ferrite rods from AM radios, search for "impeder" rods. These are 
> used for induction welding of pipes, and can stand high power at hundreds of 
> kHz. Sometimes you can get them cheap on auction sites.
>
> I use one to match my 40m longwire antenna on 630m. When tested on the bench 
> it survives 100W without problems. It also makes a nice receive antenna (few 
> of then can be stacked in a long tube).
>
> VY 73
>
> Jacek / SQ5BPF
>
>
> On Wed, 26 Dec 2018, DK7FC wrote:
>
>> Date: Wed, 26 Dec 2018 19:42:05 +0100
>> From: DK7FC <selberdenken@posteo.de>
>> Reply-To: rsgb_lf_group@blacksheep.org
>> To: rsgb_lf_group@blacksheep.org
>> Subject: Re: LF: VU2BGS
>> 
>> ...I know someone who clandestinely removed the ferrite rod of a radio of 
>> his XYL (now ex XYL) beeing able to receive the MF AM
>> broadcast. Many radios, if not to modern offer 'FM/AM' radio but AM is not 
>> used by most people. So this rod can be used to build a
>> matching unit for a 630m band antenna. And of course the core material is 
>> suitable because the antenna is used for this frequency
>> range.
>> However one has to take care that no local QRM sources are picked up with a 
>> rod. This is the disadvantage relative to a toroid of
>> course. So better place the core near the antenna, not into the shack.
>> 
>> 73, Stefan
>> 
>> Am 26.12.2018 17:03, schrieb Clemens Paul:
>>
>>       Hi Kumar,
>>
>>        >only the ferrites are a big problems here !
>>
>>       You may have a look at
>>       https://www.radio-store.co.uk/
>>
>>       They ship worldwidwe,sell also small quantities and have very 
>> competitive prices.
>>
>>       73
>>       Clemens
>>       DL4RAJ
>>        
>>
>>       >-----Original Message-----
>>       >From: owner-rsgb_lf_group@blacksheep.org
>>       >[mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Gaj Kumar
>>       >Sent: Wednesday, December 26, 2018 9:40 AM
>>       >To: rsgb_lf_group@blacksheep.org
>>       >Subject: Re: LF: VU2BGS
>> 
>> 
>
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