[ARC5] Vibrator Power Supplies

[D C _Mac_ Macdonald]

My NCX-D worked great for many years, but 
when it cratered, I could never find any 
replacement transistors that worked. 
 
I think I bought my NCX-3, NCX-A, and NCX-D 
in 1963 or early 1964. Receipt from Ed Juge 
Elecronics is around here somewhere! 
  
* * * * * * * * * * * 
* 73 - Mac, K2GKK/5 * 
* (Since 30 Nov 53) * 
* k2gkk at hotmail.com * 
* Oklahoma City, OK * 
* USAF & FAA (Ret.) * 
* * * * * * * * * * * 
 
 
> From: geoffrey at jeremy.mv.com
> To: brianclarke01 at optusnet.com.au
> Date: Fri, 7 Dec 2012 20:27:02 -0500
> CC: arc5 at mailman.qth.net
> Subject: Re: [ARC5] Vibrator Power Supplies
> 
> When germanium power transistors became available the SSB mobile transceiver 
> craze began. Two transistors, a handfull of passives and a transformer with 
> several windings would supply 200-400+ W input power that you could easily 
> hold in one hand.
> 
> I still remember the device used in the PS I helped design in 1963, the 
> 2N1519, which I said would not be reliable in an automotive charging system 
> enviroment and was proven right. This junior kid on the block, and a lowly 
> tech to boot, had suggested the 1N1521 for pennies more; the senior 
> engineer settled on the 2N1520 with a lot of hot air explanation and 
> everyone that came back for service got the 1521 and so did production. The 
> doofus never looked at a scope to see what was actually on a generator 
> output line to the battery. Alternators only became an option in 1962 and 
> mostly standard in 63 but were still far from clean.
> 
> The switcher didnt get traction until many years later for high voltage and 
> power in consumer equipment.
> 
> 
> 
> ----- Original Message ----- 
> From: <brianclarke01 at optusnet.com.au>
> To: "D C _Mac_ Macdonald" <k2gkk at hotmail.com>
> Cc: "ARC-5 Mail List" <arc5 at mailman.qth.net>
> Sent: Friday, December 07, 2012 5:59 PM
> Subject: Re: [ARC5] Vibrator Power Supplies
> 
> 
> > Dynamotors typically have a conversion efficiency of no more than 50%. A 
> > vibrator supply can reach 70% easily, and often more, if designed 
> > properly. The modern day development of the vibrator is the switched-mode 
> > power supply, which often reaches in excess of 95% efficiency.
> >
> > I suppose when fuel was plentiful and cheap, what did it matter if you 
> > consumed a gallon to do a job that a quart could do?
> >
> > Then you need to consider the downstream effects - the filtering 
> > components for a dynamotor are much smaller and lighter than for a 
> > vibrator, because of the frequency. But with SMPSUs, operating at 1 MHz or 
> > so, the filtering components are very much smaller than for a dynamotor.
> >
> > 73 de Brian, VK2GCE.
> >
> >
> >
> >> D C _Mac_ Macdonald <k2gkk at hotmail.com> wrote:
> >>
> >>
> >> Transmitters used higher currents than receivers
> >> and that may have come into play in some cases.
> >>
> >> However, as Richard Knoppow stated, they were
> >> probably a whole lot more reliable for a demanding
> >> application. Motor and generator theory and practice
> >> had been firmly developed and established for years.
> >> About all that could go wrong were the brushes,
> >> commutators, and armatures. Look at how simple
> >> it would be to change out the dynamotors on the
> >> ARC-5 and SCR-274-N stuff! They are also very
> >> compact, if not particularly light weight.
> >>
> >> * * * * * * * * * * *
> >> * 73 - Mac, K2GKK/5 *
> >> * * * * * * * * * * *