Point taken...
Sent from a wireless device of an unrevealed brand.
On 5 mar 2013, at 00:55, "Carl" <km1h@jeremy.mv.com> wrote:
> You sure did mention "continuous" twice and you also asked for feedback.
>
> Transformers should always be specified at CCS when ordering as reputable
> manufacturers do not work with ICAS, IVS, or other ham versions of ratings.
> What it is capable of in ham use is up to the individual.
>
> I dont see either one of those quotes being capable of 2.5-3% regulation at
> twice CCS with any sane value of filter C
>
> Carl
> KM1H
>
>
>
> ----- Original Message ----- From: "Ulf (SM0NOR)" <ulf@sm0nor.com>
> To: "Carl" <km1h@jeremy.mv.com>
> Cc: "Jim Garland" <4cx250b@miamioh.edu>; <amps@contesting.com>
> Sent: Monday, March 04, 2013 5:13 PM
> Subject: Re: [Amps] Transformer choice
>
>
> No one mentioned CCS here, Carl. I was into "ham specs" already from the
> beginning. This particular project calls for a certain level of mobility.
> Compromise is fine..
>
> Sent from a wireless device of an unrevealed brand.
>
> On 4 mar 2013, at 21:57, "Carl" <km1h@jeremy.mv.com> wrote:
>
>> I would not consider 11 kg to be close to a 2kVA CCS transformer. The
>> AL-1200/1500/82 Dahl is 15 kg and that is ICAS (2570V/800ma) and a C Core
>> yet it still has to be derated for RTTY, etc.
>>
>> A stock SB-220 transformer is close to 11 kg and its rated at 600VA.
>>
>> Also remember those ratings are DC input power, not RF out. Add 15-20% to
>> the weight for E-I construction.
>>
>> Carl
>> KM1H
>>
>>
>>
>>
>>
>> ----- Original Message ----- From: "Jim Garland" <4cx250b@miamioh.edu>
>> To: "'Ulf (SM0NOR)'" <ulf@sm0nor.com>; <amps@contesting.com>
>> Sent: Monday, March 04, 2013 7:55 AM
>> Subject: Re: [Amps] Transformer choice
>>
>>
>>> Hi Ulf,
>>> To me the choice depends on how much you trust Company B. If Company B can
>>> be trusted to meet their quoted specifications (2000VA with 2.5% voltage
>>> drop at full load), then I'd go with them. As you note, 11 kilo is as big
>>> or bigger than the transformers in many ham-rated commercial amps of the
>>> same power rating. If you're planning on heavy contest use, or RTTY
>>> service, then Company A is probably the better choice, but for routine ham
>>> operation I'd think Company B makes mores sense, considering the large
>>> price differential. An interesting choice.
>>> 73,
>>> Jim W8ZR
>>>
>>>
>>>> -----Original Message-----
>>>> From: Amps [mailto:amps-bounces@contesting.com] On Behalf Of Ulf (SM0NOR)
>>>> Sent: Monday, March 04, 2013 4:29 AM
>>>> To: amps@contesting.com
>>>> Subject: [Amps] Transformer choice
>>>>
>>>> Hi Guys,
>>>> I'm looking for some feedback on two transformer offers I have. I'm
>>>> intending to build a
>>>> table top amp, so I'm accepting some compromises regarding the
>>>> transformer. I have made
>>>> inquiries to a couple of winders and I have boiled them down to 2 offers.
>>>> I was asking for
>>>> 2000 Volts @1A =2000VA (+ G1 and G2 windings). I'm targeting to get
>>>> 2200-2400 watts
>>>> output in PEP service and about 1K in continuos service.
>>>>
>>>> Both companies claim 2000VA but at different core weights
>>>>
>>>> Company A:
>>>> 17 Kilo toroid, D=200 mm, H=110. About 3% voltage drop at full load. Max
>>>> temp rise =
>>>> 105C over 40C ambient. DC resistance, about 25 ohms.
>>>> Price: €480
>>>>
>>>> Company B:
>>>> 11 kilo toroid, D=180 mm, H=85mm. About 2,5% voltage drop at full load.
>>>> Can't, or don't
>>>> want to specify other data.
>>>> Price: €195
>>>>
>>>> So what are your reflections? The A is obviously a the better choice. They
>>>> are serious and
>>>> they offer detailed specs, exact delivery times etc. But all comes at a
>>>> premium price.
>>>> Company B is smaller and they obviously compromises with their
>>>> specifications, but the
>>>> price is a lot lower and so is the weight.
>>>>
>>>> Now, I don't expect the cheaper and smaller core to do wonders. The bigger
>>>> one will for
>>>> sure be more rugged and closer to "true 2000VA", especially if I run it in
>>>> true continuous
>>>> mode. I'm inclined to go for the the bigger one, because I want the best.
>>>> But OTOH, I don't
>>>> want to waste money because of a "feeling". Perhaps the smaller one will
>>>> be enough given
>>>> the table-top size/PEP service I'm targeting? After all, it matches what's
>>>> inside most
>>>> commercial amps in this category.
>>>>
>>>> I'm happy for any feedback...
>>>>
>>>>
>>>>
>>>> 73's
>>>>
>>>> Ulf (SM0NOR)
>>>> ulf@sm0nor.com
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> Amps mailing list
>>>> Amps@contesting.com
>>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
>>> _______________________________________________
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>>> http://lists.contesting.com/mailman/listinfo/amps
>>>
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