[Amps] Expert 2K

Tue Mar 5 11:26:41 EST 2013

I've owned a 2K-FA for about 14 months now and it has been literally 
trouble-free.  (It was delivered with one of its six output ports 
inoperative.  The US distributor offered to repair it for me while I was 
visiting the Orlando Hamcation, but I declined the offer.  I didn't need 
the additional port and didn't want to drag the unit down to Orlando, 
although it weighs only 44 pounds and comes with a carrying case.)

I can't comment on the QSK performance because I never use it.  While I 
admit my hearing isn't what it used to be, I do not find the fan noise 
very noticeable at all.  I have the fan set to routinely come on when I 
switch from STANDBY to OPERATE.  My only objections are that the key 
down time with 1,500W output is about 10 seconds before it reverts to 
the next lower output level (1,000W) and that there's no service manual 
available. However, I have never had a problem in routine CW  I can't 
seem to locate the data that I generated regarding downward power drift 
on lengthy transmissions, but my recollection is that it wasn't very 
serious and amounted to 25-50W and stopped after the first few seconds 
of transmission.  (I should point out that the overwhelming proportion 
of my operation is CW.)

The local distributor, Expert USA, is located in Texas as is the service 
guy.  The Steppir Antenna folks were the original distributors but 
severed the relationship for unknown business reasons.  These units seem 
to be very popular in Europe and, from what I can gather, the 
manufacturer is having no problems selling them.  Admittedly, they ain't 
cheap: about 7200 USD.

73, Joe
K2XX

On 3/4/2013 11:26 AM, Paul Christensen wrote:
> I saw the SPE 2K amp at last year's Orlando Hamcation.  Overall build 
> quality is excellent -- like the smaller 1K-FA.  SPE has addressed the 
> QSK problem that plagued early 1K units although they appear to be 
> using frame relays rather than vacuum types.  When the amp is engaged 
> in Tx, the T/R relays operate so that the coils are not energized and 
> use the NC contacts. This, in attempt to better the relay's activation 
> time instead of using a coil accelerator circuit.
>
> I have no issues when using the higher quality frame relays, but my 
> first choice is either a vacuum relay or PIN diodes, despite predicted 
> inferior lifetime of the vacuums and the care required with PIN 
> design.  SPE was considering a vacuum option but I'm not sure that 
> materialized.
>
> Fan noise remains a concern although I believe they're using a 
> high-volume solution across the heat sinks.  Output power with my 
> 1K-FA decreases by ~10% as the PA decks heats up.  Not a big issue but 
> that's an area of improvement needed with all commercially made 
> solid-state amps.  Their fault circuit design is excellent.  
> Essentially more than a half-dozen sample points are continuously 
> checked and summed.  Any fault immediately deactivates MOSFET bias and 
> writes to an error log.
>
> It's nice to have the instant-on power of the 1K-FA but its no 
> substitute for a well-designed VT amp.  I'm using a PIN diode 
> "wrap-around" circuit as described on my QRZ.com page.
>
> Paul, W9AC
>
>
> ----- Original Message ----- From: "Jim Thomson" <jim.thom at telus.net>
> To: <amps at contesting.com>
> Sent: Monday, March 04, 2013 11:04 AM
> Subject: [Amps] Expert 2K
>
>
>> Interesting in that they list even less specs than the Icom.
>>
>> Carl
>> KM1H
>>
>>
>> ----- Original Message ----- From: "Paul Baldock" <paul at paulbaldock.com>
>> To: "Jim Thomson" <jim.thom at telus.net>; <amps at contesting.com>
>> Sent: Thursday, February 28, 2013 12:38 PM
>> Subject: Re: [Amps] 813 efficiency
>>
>>
>>> Checkout the Expert 2K. Full legal limit even on 6M. A piece of 
>>> beauty to
>>> behold.
>>> http://www.expertampsusa.com/ExpertAmps2K.pdf
>>>
>>> - Paul KW7Y
>>
>> ## I was sure that array solutions sold these amps... but not listed.
>> How much do these amps cost ?
>>
>> ##  Being made in italy,  I would be leery of buying into a gong show,
>> if problems arose, or warranty work had to be done..or if parts not 
>> available
>> years down the road.....or if they went outa business. .
>>
>> ##  I see no IMD specs. What is the imd3 and imd5 ?
>>
>> later... Jim  VE7RF
>>
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