[Amps] NXP 65V LDMOS 1K80H-1800W

kstover at ac0h.net kstover at ac0h.net
Mon Dec 25 10:02:19 EST 2017

I did not even bother with eBay as no  manufacturer will source parts from

I did find an 3CX1500A7 on eBay for $1775. 10 people are actually watching


If I'm buying a new amplifier for $8K (Alpha 9500) it better haver a brand
spanking new tube in it.

How can you tell by looking at it that a tube is NOS or used?


Ameritron's plain Jane AL-1500 with an Eimac tube is $900 more than the same
amp with the Chinese tube, so there is a sizable premium.


Either way tubes are on their way out of the amateur market

What are we down to now for tube amp manufacturers? One and a half,
Ameritron and Alpha?

There has been two new tube amps brought to market in the last 15 years, the
Alpha 9500 and 8410 but it doesn't count because it uses those pesky evil
Chinese tetrodes. Other than  that they've  ALL been SSPA's. The top of the
line SPE and the KPA1500 include auto-tuners. The one in the Elecraft is


From: Jim W7RY [mailto:jimw7ry at gmail.com] 
Sent: Sunday, December 24, 2017 8:30 PM
To: kstover at ac0h.net; 'Amps group' <amps at contesting.com>
Subject: Re: [Amps] NXP 65V LDMOS 1K80H-1800W


How much for an 8877? And this is a 3CPX1500!



1> &_trksid=p2047675.c100005.m1851



Hardly $1399.00



Jim W7RY

Merry Christmas



-----Original Message----- 

From: kstover at ac0h.net <mailto:kstover at ac0h.net>  

Sent: Sunday, December 24, 2017 8:09 PM 

To: 'Bill Turner' ; 'Amps group' 

Subject: Re: [Amps] NXP 65V LDMOS 1K80H-1800W 


What happens when they quit making tubes?

I can think of one company making a CCS rated tube final amp (Alpha) and

they are hanging on by a thumb nail with their $6K amplifier. The 9500 won't

do CCS RTTY or FM at 1500 watts without auxiliary cooling for the power



Ameritron amps are not CCS rated, read the manuals. OM Power may be CCS

rated but they use those evil noisy Russian tetrodes. The blowers in these

amps are all famous for sounding like a Bell Jet Ranger lighting up but it's

the noise that SSPA's make that always gets thrown out. Elecraft is testing

a new cooling system for the KPA1500. New fans that turn slower, make less

noise and cool the amp just as well.


Any company producing an SS amp running 1.5Kw out with just one of these

LDMOS devices are idiots.

Everybody but SPE are using two.


I just looked at the price for a new matched pair of RF Parts 3-500ZG's.

$400. A new Eimac 8877 will set you back $1399, a pair of the these LDMOS

devices, depending on dissipation and voltage rating are a push for a pair

new 3-500's. These are all new prices. 


The Chinese versions of the tubes are cheaper, about 50% cheaper, but they

could be gone tomorrow depending on which way the wind blows.


Point to all this is SSPA's are the future, like it or not.


-----Original Message-----

From: Amps [mailto:amps-bounces at contesting.com] On Behalf Of Bill Turner

Sent: Sunday, December 24, 2017 5:16 PM

To: Amps group <amps at contesting.com <mailto:amps at contesting.com> >

Subject: Re: [Amps] NXP 65V LDMOS 1K80H-1800W


------------ ORIGINAL MESSAGE ------------(may be snipped)


On Sun, 24 Dec 2017 08:49:23 -0800, Jim wrote:


>##  I would like to see what both these amp manufacturers  have to say

about  duty cycle.  

>If they are  1.5 kw  ICAS,  I will pass on em for now, not for the $7K

price tag. 




Before anyone gets too enraptured over SS amps, you might want to reconsider

the advantages of tube type amps:


1.  With a pi or pi-L tank, no antenna tuner is required up to SWR of about



2.  Likewise, no low pass filters.


3.  Much more resistant to accidental overloads. 


4.  Heat dissipation is easy. 


5.  Usually cost less unless you want autotune. 


6.  1.5 kW CCS is easily achievable, i.e. a single 8877 pr pair of 3-500Z's.

The most common limiting factor is the power supply, not the tube. 




1.  Warm up time with some tubes. Not an issue with 3-500Z's or other

filament-type tubes.


2.  The cheaper ones are all manual tune.


You pays your money and takes your choice. 


73, Bill W6WRT




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