[Amps] NCL 2000?

[Joe Subich, K4IK]

If one needed to replace the 2x8122, it might be worthwhile looking 
at the Svetlana 4CX400.  The tube is spec'd for 600 watts out in 
ICAS ... 1200 Watts for a pair ... with 2500 Volts on the plates. 
At slightly reduced plate voltages (2200 Volts), a pair are rated 
for 800 Watts CCS.   

73, 

   ... Joe, K4IK 
   

> -----Original Message-----
> From: amps-bounces at contesting.com 
> [mailto:amps-bounces at contesting.com] On Behalf Of Skram, Helge (MED)
> Sent: Tuesday, September 30, 2003 9:31 AM
> To: Steve Katz; 've7avv at shaw.ca'; amps at contesting.com
> Subject: RE: [BULK] - [Amps] NCL 2000?
> 
> 
> My advice is:
> 
> Don't convert from 8122 to 4CX250b. I am aware that many get 1kw 
> out of these, but the signal is not linear.  The anode voltage 
> will be far beyond the max spec for the 4cx250b.  In the long run, 
> reduced reliability will easily offset the price difference.
> The 2x8122 is designed to run 1kw output, see RCA/Burle dataseets, 
> the 2x4cx250b is not.
> 
> 
> 73 de LA6MV
> Helge
> 
> -----Original Message-----
> From: Steve Katz [mailto:stevek at jmr.com]
> Sent: 29. september 2003 16:46
> To: 've7avv at shaw.ca'; amps at contesting.com
> Subject: RE: [BULK] - [Amps] NCL 2000?
> 
> 
> It's a very pretty amplifier that is, of course, also quite 
> old, c. 1966 or
> so.  As such, if it has its original filter capacitors they should be
> replaced, along with their equalizing resistors.  The 8122 
> replacement cost
> is scary, but many have converted to other tubes 
> successfully.  One recent
> conversion we did was to create a 6m monoband amp from an NCL2000 and
> because the tubes were weak, the final conversion involved 
> replacing them,
> and their sockets, with 4CX250Bs -- still puts out a kW on 50 
> MHz, with much
> more available (and cheaper!) tubes.  Small power supply mods 
> are required
> for that, but they're easy and inexpensive.  The original circuit has
> untuned input, swamped by a resistor bank.  One drawback to 
> most amps of
> this era, including the NCL2000, is no 160m coverage.  -WB2WIK/6
> 
> 
> > I'm looking for comments (pro and con) regarding the NCL 2000 amp. I
> > have an opportunity to buy one dirt cheap and aside from 
> the cost of the
> > 8122 tube, I'm wondering if there is anything else I should 
> be aware of
> > with this box?
> > 
> > 73 de Paul, VE7AVV
> > StoneyGround Station
> > -|<*><*>||<*><*>||<*><*>||<*><*>||<*><*>||<*><*>||<*><*>||<*><*>|-
> > "All email from this address is checked by Norton AntiVirus 2003"
> >  
> >  
> > 
> > 
> > _______________________________________________
> > Amps mailing list
> > Amps at contesting.com
> > http://lists.contesting.com/mailman/listinfo/amps
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>