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THE AM BULLETIN BOARD => QSO => Topic started by: w1vtp on August 13, 2010, 11:23:16 PM



Title: My Mobile "KW"
Post by: w1vtp on August 13, 2010, 11:23:16 PM
Well, not really.  But I was amazed when I pulled the cover off the PS to see that 1 AMP HV XFMR!  I now have a healthy respect for the PS.  Wonder how much carrier power I can run on AM if I put lots of blower in the HA 14?

When I ran it back in the 70's I remember the amp really got hot.  I had to blow it or it would've scorched the paint job.  That amp has seen little use. Can't wait to get it back on the air.  That's my old work bench back in service after +25 years.

Al


Title: Re: My Mobile "KW"
Post by: KA0HCP on August 13, 2010, 11:51:28 PM
You could brew a pot of coffee on that in just a few exchanges!


Title: Re: My Mobile "KW"
Post by: WQ9E on August 14, 2010, 06:30:29 AM
That is a serious supply, much beefier than the official Heath supply.

I have a little fan on my Heathkit "compact KW" and use it with HR-20/HX-20 mobile twins (but not mobile)!  The HA-14 generates a lot of heat and without a fan you want to keep the duty cycle low.  You will note scorched paint above the 572B tubes in pretty much every one you see.  With a suitable fan and your HB supply it should be able to run at SB-200 ratings.  With AM and no fan keep a chisel handy for chipping the melted tube envelope drips off your operating table :)

I have run my KL-1 "Chippewa" on AM driven by an Apache but I have never tried AM with the HA-14.  It might be OK with controlled carrier from a DX-60, Knight T-60, or Drake 4 line.


Title: Re: My Mobile "KW"
Post by: K5UJ on August 14, 2010, 08:35:39 AM
Ah, Al, you have the immortal "Kompact Kilowatt"  (That's compact with a K)  The K.K. is the stuff of every ham's dream if he dreamt of running a Kw mobile.   I once worked W6AM on 20 m. when he was running a kw from his Eldorado when he was rolling down the Hollywood Freeway, on CW of course since I am not sure Don worked any other mode, but I think he was running some kind of Swan gear. 

Anyway, it says on the front panel "SSB amplifier" or something to that effect, and if there were ever an amp to take that literally, I think this is it.  Otherwise, I'd have a big box fan under the whole amp blowing up through it.

Are those filter caps in the power supply good?  They look kind of old to me.


Title: Re: My Mobile "KW"
Post by: W2PFY on August 14, 2010, 11:55:55 AM
It will be interesting to see how these Hi Power amps will react with the auto's on board computer.

On the East coast mainly in N. E. there are a few guys experimenting with AM linear mobiles with solid state AB-1 amps. Bob K1KBW I believe has one in his car and while I haven't talked to him directly, it appears they are getting about 300 watts carrier with these home brew linear machines.


Mayhaps someone else knows more about their progress? 


Title: Re: My Mobile "KW"
Post by: w1vtp on August 14, 2010, 11:57:18 AM
Guys

It really is a hot tamale! I've always run a fan on it.  I tried using it on RTTY at 200 watt carrier and stopped doing it when things got suspiciously smelly ;D

The band switch detent got frozen so I disconnected it and can change bands but now an accidental tweak would cause some unwanted excitement.  Gotta heat up that bearing to loosen up the dried grease so I wont have that problem.  Otherwise -- anyone have the companion solid state power supply they want to part with (working or not)

Thanks for the comments, Al


Title: Re: My Mobile "KW"
Post by: Pete, WA2CWA on August 14, 2010, 12:58:02 PM
The Heathkit HP-14 is the matching mobile power supply.
The Heathkit HP-24 is the matching AC power supply.


Title: Re: My Mobile "KW"
Post by: WQ9E on August 14, 2010, 02:28:44 PM
Al,

Reading the info on the net, there were a lot of problems with the original HP-14 supply and it sounds like it was extremely temperamental.  You might be a lot better off homebrewing one using more modern and reliable components.  Some of the newer 12 volt to 120 volt inverters are supposed to produce a pretty clean waveform so you might also think about using one of them with your AC supply if you have room in your mobile setup.  I doubt if the original DC to DC supply was as efficient as modern switchers so you may get nearly the same efficiency using an inverter to feed your AC supply as provided by the original HP-14.

I have had good success using my American Beauty iron to heat shaft bearings and then I feed in synthetic motor oil (I use 5W-20) as it cools.  A couple of heat/oil impregnation cycles has worked fine for me.


Title: Re: My Mobile "KW"
Post by: w1vtp on August 14, 2010, 07:01:21 PM
Al,

Reading the info on the net, there were a lot of problems with the original HP-14 supply and it sounds like it was extremely temperamental.  You might be a lot better off homebrewing one using more modern and reliable components.  Some of the newer 12 volt to 120 volt inverters are supposed to produce a pretty clean waveform so you might also think about using one of them with your AC supply if you have room in your mobile setup.  I doubt if the original DC to DC supply was as efficient as modern switchers so you may get nearly the same efficiency using an inverter to feed your AC supply as provided by the original HP-14.

I have had good success using my American Beauty iron to heat shaft bearings and then I feed in synthetic motor oil (I use 5W-20) as it cools.  A couple of heat/oil impregnation cycles has worked fine for me.

Rodger

Thanks on the tips.  I would be most interested in any info anyone has on these inverters.  Although I must say I think I would need to upgrade my alternator before I do anything.

On the bearing problem.  Thanks for the tip.  I didn't think of using an iron.  I have one that might fit the bill.  I will try it and let this forum know

Thanks, Al


Title: Re: My Mobile "KW"
Post by: Pete, WA2CWA on August 14, 2010, 07:14:51 PM
Inverters: http://www.tripplite.com/en/products/power-inverters-chargers.cfm?gclid=CLO5qY6MuqMCFWBd5QodtWH0ag


Title: Re: My Mobile "KW"
Post by: Opcom on August 14, 2010, 07:40:10 PM
Ages ago at a hamfest there was a guy running a modified one of those on 10M SSB and CW. He had gutted it partly and added another tube, monobanded it, and had a 100A leece-neville alternator under the hood of the blazer and three little 400Hz transformers there and a 3 ph bridge rectifier. He claimed it would put out a KW PEP on sideband and said it would melt down on AM or if the key was held too long.


Title: Re: My Mobile "KW"
Post by: WQ9E on August 14, 2010, 07:49:11 PM
Al,

You probably will need an upgraded alternator to safely run this kind of power in a mobile setup.  A dual battery setup would also be helpful.  Some of the recent diesel pickups are perfect for high power mobile since they have dual batteries as standard equipment and you can generally get a snow plow prep or similar package with either dual alternators or a single very high capacity alternator.  Unfortunately with the latest emissions requirements the engine controls are about as complex as those for gasoline engines so RFI to/from is a concern.


Title: Re: My Mobile "KW"
Post by: w1vtp on August 15, 2010, 07:21:42 PM
Ages ago at a hamfest there was a guy running a modified one of those on 10M SSB and CW. He had gutted it partly and added another tube, monobanded it, and had a 100A leece-neville alternator under the hood of the blazer and three little 400Hz transformers there and a 3 ph bridge rectifier. He claimed it would put out a KW PEP on sideband and said it would melt down on AM or if the key was held too long.

Man!  I would love get info on the power supply lashup.  I've read articles in the past on the Leece-Neville 3 phase alternator -- taking the output directly out and going into a transformer and then rectified.  Think it's in a 1958 QST -- gotta check that out.  Sounds like the preferred way to do things.

Maybe I should just strap a Honda generator on the roof of my Van and be done with it  ;D


Title: Re: My Mobile "KW"
Post by: WQ9E on August 15, 2010, 08:23:21 PM

Maybe I should just strap a Honda generator on the roof of my Van and be done with it  ;D

Al, go vintage like the WWII SCR-299.  Just hook a K-52 trailer with the PE-95 generator behind your van.

There are a couple of CQ articles that also use 3 phase alternator to transformers, I will dig those out over the next few days and send scans to you.


Title: Re: My Mobile "KW"
Post by: WA1GFZ on August 15, 2010, 09:51:45 PM
I remember that article. You need 3 transformers off the windings. maybe rectify each one and series the voltage??? 3 heater transformers.


Title: Re: My Mobile "KW"
Post by: ke7trp on August 17, 2010, 08:50:20 PM
Here is a mobile 16KW rig and you get a Free Van in the deal. 

http://cgi.ebay.com/GMC-CUSTOM-VAN-HEATHKIT-LINEAR-AMP-/180542653677?pt=LH_DefaultDomain_0#ht_610wt_1137
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