Kris Power Pump Upgrade/ Restoration

[Onelasttime]

I know now that I am old have 3 kids and no life I do not know anyone that can set me up! LOL I no longer work in automotive or aviation industry either I work in health care now! LOL So no hook up's! When I worked in large industry the stuff that was thrown away was a real paradise for an old dumpster diver like me! LOL I have bearing steel scraps from roller bearing and axle manufacturing, H100 steel from submarine scrap, spring steel scrap from repairing parts tumblers and vibrators, and other industrial scrap but when it is all gone I have no source for more! LOL I have not an an electrical component hookup in at least a decade! When I worked as an engineer in Telcom I had so much iron work scraps, thread stock, 0/0, 0/1 aluminum wire, prefab cooper jumpers with hi end connectors on each end and on and on.....That was before World Come fell so all of those scraps are gone. Everyone I know has either died or moved many states away from Michigan. A few years back about 1/2 of the population of Michigan left to find work in other states!

 

[2315 Robert]

OLT, myself and the folks I work with are recycling(scavangers). We struggle to find anything good at this point. There is nothing left here pillaged(CA en-tilted attitude). When I look at the GSA auctions all items "in need of repair" CA wins. I would have to say that the folks in CA are no where near as honest as say folks in Texas. Picked up comm. equipment from El Paso still in certification. I sure there is some amazing stuff that just gets thrown away "because it is broke" (or worse). For the sake of not having to do the paperwork to excess the property. Yes, I am older with kids attempting to advise them that we are not a throw away society. The people that sell stuff make want make them believe "replace not repair". That is where we are at as a society. Buying junk for cheap and when it fails, so cheap it cost less than repairing. Like minded people on the other side of the country.

 

[Onelasttime]

I know when I was a kid Popular Mechanics and Popular Science taught us how to re-purpose things. Old TV's that where trashed where striped for expensive diodes, tubes, transformers speaker amplifiers etc....Old Lawn Mowers where picked up repaired and sold, knives made from scrap lawn mower blades, how to make your own chemical cleaners, stripper and such from common chemicals dirt cheap instead of buying pre-made stuff. My dad bought used car's that had a burnt valve or needed to have it's carb rebuilt etc....This allowed you to buy car's that where not that bad cheap but needed some work. Your labor paid off huge in savings! So yes I think a man should try to be the master of his world and should try to learn and understand all he can for his entire life time. Constantly. I can not recall how many times shoe leather, rope, coffee cans and other scraps where used to make gaskets for things. Even as a young apprentice you often made gaskets from bulk materials and used a hand crank gasket cutter even small parts like nuts, bolts, shims washers would often be fabricated. As a young Automotive Technician Apprentice in Germany I had to make a fender for a Volkswagen Beetle from a sheet of steel with English Wheel, Plensihing Hammer. Lead Shot filler leather bags etc.....I think I was 11 or 12 and my Dad taught me how to use dimensional lumber to make makeshift body dollies and how to shape a cheap hammer with a file to make it into a specialty hammer on the cheap.

When our TV broke Dad went to the library checked a broke on TV repair and taught himself how to trouble shoot the tv and repair it. He then bought the parts it needed from Sears or Radio Shack can not recall which and repaired it. Sure we did not have tv while dad was reading the book and learning but it was not that long!

The bigest obstacle today is getting a device open with out breaking the case. Gone are screws that easily allowed you take things apart to repair them. Now everything is plastic and heat stacked or has built in snap together clips that seldom allow you to open them with out them breaking or becoming too bent to hold the case snugly ever again!

 

[Shadetree Mechanic]

Bringing back an old thread in order to hopefully get some advice on optimizing this tiny beast.

I have been using the amp on and off for a couple of years now, and have noticed that it just won't modulate a full 4x the dead key on AM no matter what you drive it with.

i also think that the tubes should put out a bit more than they are.
(i have tested this amp with three different sets of tubes and the output is always about the same)

right now, on AM with a 3 watt deadkey, i get a 50 watt carrier and about 100-110 watts modulated.
the radio is tuned on the scope for 100% modulation and shows a 3 watt deadkey modulating to 12 watts.

if i decrease the drive to 1 watt, i get a 30 watt carrier, and the amp modulates to 60-65 watts.

If i drive it with a 4 watt carrier, it will key up with a 65 watt deadkey and modulate to 120-130 watts.

on SSB i get a 120 watt PEP output with a 15 watt input.

so, what is it about this particular amp that won't allow it to fully modulate an AM signal so that the peak is 4x the carrier?

also, i would think that with three tubes in parallel, that i should be getting about 180-200 watts PEP out of this amp with the input levels i am giving it.

any ideas on the low output level?

The input to this amp sits at an SWR of about 1.3:1 and did not lower the output of the amp when tuned.

I have posted the schematic i drew up to build this amp, and the only difference from the schematic to the amp as it is now is that there are caps and resistors on the rectifier diodes and the cap that couples the output of the tubes to the pi network.
that cap is now .002uF instead of .001uF.

I have spread and contracted the coil on the pi network and that only serves to move the peak around on the air variable tuning caps.

I have attached the schematic and am hoping someone can see where i could have done better.

thanks for any and all input!
LC

How much power did the driver tube put into the final tubes? Without the driver tube, maybe it needs more drive from the radio? My Context 500 amp has 1 driving 4 and does 200w dead key and only swings to about 375w and this is with a Stryker 440 that really swings and is turned down to about 5w. I can make it do 400w with no swing. I always hear people say 1:4 but I don't know what it takes to get it. I am interested to see if you have come up with a solution for this. I am definitely looking at changing the bias in mine.

 

[Onelasttime]

To be honest I can not recall. I also had a Kris Boomer and 1x3 6MJ6's was crazy power if you ran it hard I think I actually got 400 watts out of it once and I never did that again. I would let it swing to 100 most often when I used it and 200 on SSB. I do not run my gear hard at all prob. why I have never blown a transistor in the pre-driver, drive or final on any radio I have owned and I tend to own radio's 10 years or more before I trade, sell or they get stolen! LOL I have also never blown a tube in anything I started out with new tubes in. On the other hand, I have bought used amps before where the tubes were already blown in them or you powered it up and poof. For many years I did not even own a watt meter since I only operated mobile. I either had access at work or at school to equipment.

In fact, when I am setting up my gear if I have a device that can do 200 watts rms I will set it up so that it never does more than 100 watts RMS with any external controls cranked full tilt and the drive I am putting in. Once in a while I will set one up for it's true clean peak and then run the rf power at 12 O'Clock and let it swing. The problem with doing that though is that most people can not keep there foot off the gas and if you have an amp downstream and you forget to turn the power down before you flip the switch "poof"!


Clean cool electronics loafing along! That is how you sound good and have your gear last forever.