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 <[email protected]>
Reply-To: [email protected]
To: [email protected]
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 <[email protected]>
Reply-To: [email protected]
To: [email protected]
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: [email protected]
>[mailto:[email protected]] On Behalf Of Gaj Kumar
>Sent: Wednesday, December 26, 2018 9:40 AM
>To: [email protected]
>Subject: Re: LF: VU2BGS
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