Date: Sun, 12 May 2019 11:45:32 +0100
From: Chris Wilson <dead.fets@gmail.com>
Message-ID: <1272443356.20190512114532@gmail.com>
To: DK7FC <rsgb_lf_group@blacksheep.org>
In-Reply-To: <5CD714A4.5080309@posteo.de>
References: <477297345.20190414143742@gmail.com> <5CB35457.9060303@posteo.de> <592014641.20190414170848@gmail.com> <5CB37097.90104@posteo.de> <853391954.20190509134230@gmail.com> <5CD42C82.80906@posteo.de> <1562754668.20190509154749@gmail.com> <5CD714A4.5080309@posteo.de>
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Subject: Re: LF: Another impedance matching question. Paul's audio amps.
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Hello Stefan,

No, not yet, I need to finalise the positions for the ground rods. Can
I initially lay insulated stranded but each single core UK 15 Amp
mains wires on the ground's surface to the rods? Is 50 yards earth rod
spacing adequate and should I try to get them in a ditch that's
usually constantly wet? I picked up my amp a few weeks back, it looks
quite a beast! Thanks Paul Nicholson :) Toroids should land this week.

Saturday, May 11, 2019, 7:29:56 PM, you wrote:

> Hi Chris,

> Did you already lay out wires? And did you already get the amplifier?

> 73, Stefan

> Am 09.05.2019 16:47, schrieb Chris Wilson:
>>
>> Hello Stefan,
>>
>> Thanks,  ordered 3, so get free shipping, it was cheaper than ordering
>> 2 and paying shipping :)
>>
>> Thursday, May 9, 2019, 2:34:58 PM, you wrote:
>>
>>    
>>> Hi Chris,
>>>      
>>    
>>> I would not recommend the one you selected because it has an unnecessary
>>> large inner diameter and a  lower height, thus a lower AL value.
>>>      
>>    
>>> I think this is the same one that i recommended from Bürklin:
>>> https://www.mouser.co.uk/ProductDetail/EPCOS-TDK/B64290A0699X830?qs=sGAEpiMZZMs2JV%252BnT%2FvX8Df1W1GtRs010YpcsJh6dvk%3D
>>> It is also cheaper.
>>> There are other materials available, such as T65, T38, T37, offering a
>>> higher AL value. Maybe these are even more suitable at that sort of
>>> frequency but i didn't spend too much time to select the best core for
>>> each frequency. I use the N30 material from 1 kHz to MF at high power (
>>>      
>>   >>  1 kW for one core) without problems. So this is what i recommend. It
>>    
>>> will work.
>>>      
>>    
>>> 73, Stefan
>>>      
>>    
>>> PS: If you want to bridge one of Paul's 2x 7.2 kW amps, you may need two
>>> of them ;-)
>>> PPS: You may want to build two orthogonal ground loops then, one per
>>> channel. With SpecLab you can then drive each channel separately and so
>>> you can build a software rotatable loop by aligning the phase between
>>> the channels, while staying into the shack when its cold and/or rainy :-)
>>>      
>>
>>
>>    
>>> Am 09.05.2019 14:42, schrieb Chris Wilson:
>>>      
>>>> Hello Stefan,
>>>>
>>>> I  am  now on to building a matching transformer but it seems Buerklin
>>>> have  a  minimum  order  of  60 units! I have found this bigger core at
>>>> Mouser, could I use that instead please?
>>>>
>>>> https://www.mouser.co.uk/ProductDetail/EPCOS-TDK/B64290L0730X830?qs=4l9S5vBWkUJtsO6ZFRCS4g%3D%3D
>>>>
>>>>        
>>
>>
>>
>>    


-- 
Best regards,
 Chris                            mailto:dead.fets@gmail.com