| Author |
Message |
    
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 67
Registered: 1-2006
| | Posted on Saturday, April 22, 2006 - 3:19 pm: | 
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first of all we've been getting alot of smoked amps, mostly from export radios.
we find it funny that most guys have no problem diving a radio with several hundred parts but,
won't tune an amp with less than like 50 parts.
seem's to be this oria about them.
right now i'll stick to a 2 pill.
but most amps are the same.
unsted of turning the radio down:
tune the amp to handle the power,
convert to high drive simply by
locating the attenuating resistor.
it's usaly a 5 or 10 watt around 50 ohm.
replace highr wattage & same value or stack "parallel"
replace with 2x watt for 2x power input.
ie..20 to 40
the math is x=(axb)/(a+b)
so stack a 50 with a 50k
this is also where you adjust swr from radio to amp.
if it has a choke usaly 220uf dido.
you can wind your own coil to "about the same math"
we could get in to that later.
next remove 1 or 2 raps from input xfmr.
here's where the swing comes from.
try 1 first see if you like...
add a rap or so to output xfmr.
wire must handle heat.
if amp has auto ssb:
need to add more time on relay.
find ele cap next to relay,
stack & switch 1 leg with 100uf "bigger # more time"
improve ears with better receve transistor
duh.
could remove more hash & trash with choke should cover 200uh & trimmer that should cover 480.@ base of receve amp.
to clean up an amp:
remove last cap on output replace with trimmer
also should cover what you removed & same or higher voltage.
there's some more but we are are only at 101.
have you noticed repeating #s & math?
73rds.... |
Patzerozero
Senior Member
Username: Patzerozero
Post Number: 2739
Registered: 7-2004
| | Posted on Saturday, April 22, 2006 - 5:03 pm: |
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most export radios already have variable rf power output control on front of radio, as well as mic gain. what those 'new' to amplifiers need to do is turn rf power & mic gain down to zero. then adjust the rf power slowly upwards til they get the carrier they require-up to the limit of the rf power transistors in the amp. then, they can adjust the mic gain upwards for the recommended max swing of the amp's power transistors. they can then turn rf power or mic gain down to reduce any interference to the neighbors. they just have to understand that once a 2 x 2879 is keying 60 watts or so-STOP, even though there is more room to turn the knob.
i think your amp mods are outside of the technical capabilities/willingness to attempt of some of those who are blowing up 250 palomars using galaxy 99's that they needed to have a tech crank up or wackpack in the 1st place.
i personally crank for maximum smoke in the shortest time, repair, then back down a notch  |
Allan
Member
Username: Allan
Post Number: 80
Registered: 2-2006
| | Posted on Saturday, April 22, 2006 - 6:34 pm: |
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Pat sez.....i personally crank for maximum smoke in the shortest time, repair, then back down a notch
Pat00, I'm sure the last section does not apply to Galaxy. Only the first part. |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 68
Registered: 1-2006
| | Posted on Sunday, April 23, 2006 - 2:45 pm: |
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willingness is more like it.
i think they get the amps later & hook-em with out a tec. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1476
Registered: 9-2004
| | Posted on Tuesday, April 25, 2006 - 10:56 pm: |
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georgeodjungle,
right on!!!
i think we really needed a thread like this.
i am OK inside a radio, but really need to learn about the amps.
if we could work with a specific amp, and mention some actual part numbers, i would be willing to do the suggested mod, and post the results.
how about the KL300p?
it seems simple, and in need of some upgrading.
tunable in and out?
better filtration?
AB1 mod? (i have ssen this here before, wondering if you do it the same)
i sure would appreciate some guidance here.
im sure there are plenty of others here that also own this amp.
thanks,
matt |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 74
Registered: 1-2006
| | Posted on Thursday, April 27, 2006 - 1:13 pm: |
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how many watts do you want to run in to it? |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1483
Registered: 9-2004
| | Posted on Friday, April 28, 2006 - 12:18 am: |
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well, for me, the input power is not the biggest deal, although i would like to know how to change it just because i like to know stuff!
so, just as an example; lets say i have a radio that deadkeys at 5 watts, and swings to 20.
can you tell me the caps in this amp (kl300p) that i would need to change to variables? in and out?
and what value of variable cap to use?
i really appreciate the lesson,
matt |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 75
Registered: 1-2006
| | Posted on Friday, April 28, 2006 - 1:02 pm: |
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here ya go!
power in:
r4 27 ohm change to at least 5 watt
this also effects swr in so if ya could find a bigenuf pot.
swr in:
remove c4 add trimmer that covers 150pf & at least 50volt.
swr out:
remove c10 change to trimmer that covers 47pf & @ least 500volt
have fun...
cerkit @ mass-elektronk.com |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 76
Registered: 1-2006
| | Posted on Friday, April 28, 2006 - 8:45 pm: |
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also,
the more i think about it:
20 watts might a lil high for that xtfmr.
if it sounds not so good do the wrap thing.
remove 1 rap from the lil transformer & add 1 to the big transformer. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1489
Registered: 9-2004
| | Posted on Saturday, April 29, 2006 - 9:54 pm: |
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sweet!!!
thanks for the info!
this is going to be fun. a couple of questions.
1. do i have to add a turn on the big one, if removing one on the small one?
or can i just remove the small wrap?
(just because i have seen advice before about only removing a turn from the small xfrmr)
2. when you say, "covers 150pF" or "covers 47pF" do you mean 0-150 and 0-47?
or is 150/47 the center of the range?
like, 0-300, and 0-94, respectively.
cant wait to try this!
it may take me a week to get to, but i will post the results. im sure there are others sandbagging here on this topic so keep the info coming!
matt |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 78
Registered: 1-2006
| | Posted on Saturday, April 29, 2006 - 9:54 pm: |
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for longer key time:
it's c3 a 33uf @ 16 volts.
i'd try a 47uf @ 16volt |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1490
Registered: 9-2004
| | Posted on Saturday, April 29, 2006 - 10:04 pm: |
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just looking at the schem. (are we using the same version? i am using version 4.10)
c4 makes sense, as it is 100pF.
C10, however, is a 33uF (microfarad) electrolytic cap.
is there a typo on this one?
can an electrolytic be replaced by a variable?
might you be referring to C12?
thanks again for the help,
matt |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 79
Registered: 1-2006
| | Posted on Sunday, April 30, 2006 - 1:52 pm: |
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c10 is for time:
you could go bigger uf with a pot.
for that varry thing.
how far have you got?
do 1 step at a time and see what it does.
looking @ the schem r3 needs to be replaced to.
1)i'd remove from the small xfmr 1st see if you like.
SWING.
then add to the big one.
then see if u likes.
your not gonna hurt nothing.
what advice have you see before?
2)i mean by covers, should be bigger than or ya center will work.
yep i'm shure there's gunnybaggen, sandbaggers,
but that's o.k. ya know them amps got juju.
might have to start another thread for that other amp.
it's the same steps,
lil dif parts....... |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1498
Registered: 9-2004
| | Posted on Sunday, April 30, 2006 - 10:31 pm: |
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i havent gotten to open the amp up yet.
i will have some free time while at work on tues afternoon to try these.
so far:
replace R4 with 5 watt version
replace C4 with 0-300pF trimmer cap.
replace C10 with 0-100pF trimmer cap.
remove one turn from input transformer.
what is the replacement for C3 for?
SSB delay time?
what would the replacement for R3 be, and whats it for?
i have seen this suggested before (the input transformer winding thing) in an old secret CB book.
it was for if you had a dual final radio, with a low drive amp.
if i am mistaken on any of this, thanks in advance for setting me straight.
matt |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 80
Registered: 1-2006
| | Posted on Monday, May 01, 2006 - 12:46 pm: |
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r3 is for low power output.
c3 yes:
if you remove a wrap,relay won't stay keyed up long enugh on ssb @ only 20 watts |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1546
Registered: 9-2004
| | Posted on Tuesday, May 09, 2006 - 5:44 pm: |
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george, wanted you to know i havent forgotten about this project.
just pulled the amp out of the car and am looking at it as i type.
im afraid we might have some part number discrepencies, as there are about four different versions of this amp.
i just found out that i for sure have verasion 3.10.
can we start over making sure to use this as our referrence?
i will try to cross referrence what we have so far if you can tell me which version you were using.
not fair to make you do all the work twice!
im going to start buying parts on friday, and will be in the process of modding over the weekend, so if you could get back to me on this before that i would appreciate it immensely.
thank you so much for your help so far!
matt |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1547
Registered: 9-2004
| | Posted on Tuesday, May 09, 2006 - 5:56 pm: |
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george,
i have been reading through the posts and im afraid im confused!
i think we have been using two different versions.
again, i have the version 3.10.
thanks,
matt |
Georgeodjungle
Member
Username: Georgeodjungle
Post Number: 99
Registered: 1-2006
| | Posted on Tuesday, May 09, 2006 - 8:16 pm: |
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no prob.
all steps are the same:
1) resistor(s) that feeds the lil transformer
2) ele cap that goes to the ssb switch
3) vary last cap that goes out to the antenna.
4) the lil transformer.
amps are prety tuff, you wont heart it
i'll look for your ver.
where can i find 3.10
you can fax or email me. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1552
Registered: 9-2004
| | Posted on Tuesday, May 09, 2006 - 11:30 pm: |
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this is getting fun!
i think ive got it all figured out so far, and i understand the concepts behind what im going to do, but looking has brought up a couple more questions.
first; here's what i have figured out so far:
(version 3.10)
change R9 to 27ohm 5 or 10 watt.
for higher input power handling.
change C17 to a trimmer cap 0-300pF (or 150+)
50 volt min. for input SWR adjustment.
change C23 to a trimmer cap 0-100pF (47+) 500 volt min. for output SWR adjustment.
change C8 from 33uF to 47uF for longer SSB delay time.
am i correct so far?
ok, the questions:
it looks to me that R9 controls the power output on the high side, and R8 controls the power output on the low side.
1. am i right?
2. would changing R9 to a lower value (same or better wattage rating) would the output power be increased?
not quite sure what these resistors jobs are all about. perhaps a short tutorial?
3. what are C10, C12, and C26's respective jobs?
can their value be increased?
4. can you recommend any transistors that might have a lower noise figure? (less noisy)
thanks once again for your time and patience,
matt |
Georgeodjungle
Intermediate Member
Username: Georgeodjungle
Post Number: 102
Registered: 1-2006
| | Posted on Wednesday, May 10, 2006 - 11:41 pm: |
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wow. you get a golden star!!!!!!!!!.
your handle should be grasshopper.
but:
2) r9 lower = lower it goes to ground.
c10 plays with swr, out.
c12 cleans up a lil & a ac thing.
theres no c26 but
c6 helps match tr3 pill
it's a 10% cap, only one reason why it lame to get "match sets"
i'll get in to that later..
baby steps,grasshopper.
please do one step at a time,
run it see what it does.
so you'll have an under standing on what your doing.
you'ld have to look up rcv tr for your self.
any better gain would work but,
you could add a choke & trimmer to hear better.
let's get done with this stuff 1st. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1559
Registered: 9-2004
| | Posted on Thursday, May 11, 2006 - 4:08 pm: |
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ok, ok, i wont get ahead of myself!
tomorrow i will be buying the trimmer caps, cap, and resistor(s) i'll need to do the things we've confirmed, and i'll be doing the project on saturday afternoon while im here at work. (lots of free time here)
so i will have the computer handy if i get stuck. it should go pretty smoothly.
two things,
there is a C26. it is just above D10 in the diagram. it is a 470uF elec. cap.
im thinking increasing its value a bit couldnt hurt.
please make sure you are looking at version 3.10.
should i add C6 to my amp?
is it something we might add later?
seems to me that it should be there, but who knows.
thanks for all the help so far.
im also going to make the receive preamp switchable, as i just had it disabled before. (on all the time otherwise)
matt |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1580
Registered: 9-2004
| | Posted on Sunday, May 14, 2006 - 6:41 pm: |
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hey george,
i got almost all the parts i needed on friday.
couldnt get the variable caps though.
get this!
its a digikey store, and they only carried ONE value of trimmer cap. 20-180pF. well, i figured that would work for me so i asked for two of them.
12.95 a piece!!!
can you believe that?!
i told the kid at the counter that that must be the 100ct. cost.
he brought out the cardboard bin with the caps in it and there were three bags of 100 labled 9.99.
i told him that the price for a 100ct. probably went up to 12.95 and that there was a mistake on the computer.
he came back and told me that the store manager told him that the price was correct and gave him some BS reason about them being used for illegal purposes and blah, blah, blah...
i told the kid that every TV has one or more in them, and left in disgust.
im done venting now!
so now im going to place an order with mouser, and i should have the caps very soon.
forgot the parts i do have at home, so i will start with them tomorrow.
later,
matt |
Georgeodjungle
Intermediate Member
Username: Georgeodjungle
Post Number: 104
Registered: 1-2006
| | Posted on Sunday, May 14, 2006 - 11:26 pm: |
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i haven't done nothing mom's day.....
you could make your own caps,chokes & resistors.
eletronics 101...
but ya.
store bought gets spendy. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1595
Registered: 9-2004
| | Posted on Monday, May 15, 2006 - 4:31 pm: |
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make my own variable cap?
my hands are pretty big, im afraid i couldnt even hold the mica!
those vari. caps were just plain mismarked.
im doing some of the mods right now.
matt |
Chad
Advanced Member
Username: Chad
Post Number: 825
Registered: 11-2004
| | Posted on Wednesday, May 17, 2006 - 11:30 am: |
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So as per KV's request I'm looking at a KL300P schematic Ver3.10. I too would like a little higher drive, class AB1, and could care less about I/O tuning.
First mod done. Remove TR3 that controls the Preamp relay. The preamp was worthless to me and caused more problems than it solved. Devil be gone!
For SSB delay I read it as upping the value of C8 which is a 33uF 16V 'lytic. C10 is 2.2Uf,,, not SSB delay. S1 is SSB delay switch right? Therefore C8 to ground and R2 would set up the RC timing. I have no problem with my SSB timing I COULD see how some could have problems. I'd go up slow like 47Uf first, etc. You don't want it too long, especially around here where people reply VERY quickly and in heavy skip where you need to get business done quick. You don't want it cutting off the first part of the reply. Heck I leave mine in SSB all the time. Again, no chatter problems, BUT I have heard it un-key a few times.
As for changing the drive..... S3 is the Hi/Lo switch. It is a godsend on the KL300P, in Hi position it's straight drive, in the Low position THE AMPLIFIER CAN STILL MAKE ALL OF IT'S POWER but is less sensitive (takes more drive) R8 and R9 set up a L-Pad circuit to reduce the amount of drive to the drive transformer, T2 in the schematic. By using an L-Pad calculator you can change the drive of the amplifier in the low position and leave it stock in the high position. Unfortunately, you need to know the impedance of the transformer (driven device) to calculate “loss” anyone care to take this measurement? I don’t have the gear to do it now. Regardless, I have found that you can drive the KL300P in the low position with 4 watts and it will key around 40W and swing to 150-160W with a solid 13.8V going into it. This is really all the farther I care to push this amp. With the amp in low position you can literally HAMMER it with SSB. Just keep an eye on your power output and if someone tells you that you are overdriving HEED THEIR WARNING. You will be surprised what you can hit it with in the "Low" setting. It can be made "lower" with a change to the L-Pad network. So think of the switch as “low” = Higher drive, it’s bakkids.
As for the AB1 mod... I totally plan to do it BUT. I tried it with the locals that are VREY picky about audio and not afraid to tell the truth. They noticed NO degradation in audio quality when the amp is in operation, it is being used with a Magnum 257 and I get GLOWING audio reports barefoot. Although I think it will give me peace of mind not running class C I thought I'd throw that in so you know it sounds pretty darn good as it stands. Lon has one on SSB and has no problems with audio either. I just want an AB amp; I DO think it may cut back on some of my front end overload problems in the home and shack, etc due to possibly less spurious output from Class C operation. (More Linear ya know?)
In George’s first post it mentions changing the attenuation resistor to one with a higher power handling but same value. I’m still scratching my head over this one. This will not change the circuit electrically, just increase it’s POWER HANDLING. Proper power attenuation requires the use of an L-Pad to achieve impedance matching. Increasing the power handling of an L-Pad by increasing the wattage of a resistor simply keeps the level of attenuation the same but allows more power to be thrown at it. In other words if the L-Pad can handle 5 watts with 5 watt resistors and provides 3dB of loss then it outputs 2.5W If you change them to 10 watt resistors then it can safely handle 10 Watts still has 3dB of attenuation and with 10 watts will have 5 watts of loss. What needs to be done is calculate the VALUE change that will allow 6dB of attenuation and STILL use 10W resistors to handle the thermal situation. Upping wattage will not increase attenuation unless the circuit is suffering from thermal run-away and at this point you have problems from the get-go. I would use the L-Pad circuit already there and modify it’s values I’m almost thinking we could assume that T2 has a 50 ohm impedance Unless the tank circuit (C3-6 and L1-4) changes or sets the input impedance of the amplifier, which I kinda doubt, it looks like an input harmonic filter to me and what sets the key circuit into action.
Thoughts?
Chad |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1625
Registered: 9-2004
| | Posted on Wednesday, May 17, 2006 - 6:17 pm: |
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ummm yeah, i will read that post a few more times thank you.LOL
i see what you mean about higher wattage resistors not changing the circuit electrically.
i increased C8 to 47uF,
and have to order variable caps for the input and output tuning.
thats what im after.
so turning this amp upside down and mounting it to the bottom of a radio would be bad eh?
what if i removed the speaker and put a fan in its place, and left the sliding metal "bottom" cover off of the amp?
also found out computer stores sell heatsink fan kits much cheaper than radio supply stores.
thanks for the input.
what would increasing the value of C26 do?
matt |
Chad
Advanced Member
Username: Chad
Post Number: 827
Registered: 11-2004
| | Posted on Wednesday, May 17, 2006 - 8:59 pm: |
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C26 is a basic filter cap to get rid of any whine or ripple in the power supply. Increasing it probably won't do much to be honest.
Go ahead and mount it to the bottom of the radio with the cover on. See if it gets hot, if it does affix a fan to the heatsink blowing at it. Modified drywall anchors work well for this  Blowing a fan at the transistors themselves won't do much as they output their heat to the die then to the heatsink. I have never gotten mine that hot as to need a fan but I run it responsibly (yeah right) for the most part. Also remember that SSB is my bag and the duty cycle is much lower as it does not have to amplify a carrier. The times I did notice it getting warm was using AM and the person was a tad too far away, I was running it pretty hard. But in Vegas heat........
Did the 47uF delay cap work out for you? Or is it still too short?
you can buy lots of fans (as in groups) on ePay and will pay more for the shippping than the fans, I'm looking for some around 2" for a car audio project I'm working on. There's tons of styles out there.
Cahd
Chad |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1636
Registered: 9-2004
| | Posted on Thursday, May 18, 2006 - 5:42 pm: |
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thanks chad,
i found a dual fan setup, already encased in aluminum at fry's for 10 bucks!
it looks identical to the ones you see on ebay for the KL amps.
i PM'd inspector to try and get him to add some input to this thread.
i found an old post of his where he talked about upgrading the feedback section with metal film caps, and better resistors, so i was hoping to get some details from him on this.
i know he mentioned changing out the three disc caps in parallel on the output transformer to a single metal film cap, but i want details.
any ideas?
havent tried the amp yet as im waiting for the trimmers. got them ordered, now i just gotta wait.
matt |
Gatorade
New member
Username: Gatorade
Post Number: 6
Registered: 4-2006
| | Posted on Thursday, May 18, 2006 - 5:45 pm: |
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HELLO. DOES ANYONE HAVE ANY INFO CONCERNING A GOLDEN FALCON MOBILE 6/6LF6 TUBE LINEAR? I WOULD LIKE TO INSTALL IT IN MY 67 C-10 PICKUP. MY RADIO IS A GALAXY77HML. ANY SUGGESTIONS CONCERNING ALTERNATOR{S}/BATTERIES etc. |
Georgeodjungle
Intermediate Member
Username: Georgeodjungle
Post Number: 106
Registered: 1-2006
| | Posted on Thursday, May 18, 2006 - 7:09 pm: |
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heat kills... |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1753
Registered: 9-2004
| | Posted on Monday, June 05, 2006 - 4:52 pm: |
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well, to bring some closure to this thread; i tried all of the changes mentioned, except the AB bias mod.
the amp is now back to stock as it didnt work with the variable input output tuning and the swamping resistor change.
i did leave the SSB delay cap mod in because i like the way it works.
i also added a fan and a switch for the preamp which all work well.
so, the amp works, but if you want to tune the input and output, its best to solder in a new cap and see how it does rather than change to a trimmer.
just my findings,
thanks to all who helped and advised on this one; i learned alot, and thats the real point!
later,
matt |
Chad
Advanced Member
Username: Chad
Post Number: 903
Registered: 11-2004
| | Posted on Monday, June 05, 2006 - 10:10 pm: |
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Cool! Glad you did not mess it up and got it working! I upped my SSB cap too this weekend but stumbled on the AB mod. I was not comfortable with the heat production of the ceramic resistor so I'm getting one to mount to the heat sink.... somehow
Chad |
Georgeodjungle
Intermediate Member
Username: Georgeodjungle
Post Number: 114
Registered: 1-2006
| | Posted on Wednesday, June 07, 2006 - 12:32 pm: |
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hay kv:
what did you not like about the high(er) drive convert?
i know the tune thing takes some patients. |
Kid_vicious
Senior Member
Username: Kid_vicious
Post Number: 1777
Registered: 9-2004
| | Posted on Wednesday, June 07, 2006 - 11:36 pm: |
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well, i didnt do it in steps like i should have, so it was hard to say what caused the lack of output.
thats why i just put it back to stock.
i only dead key at 2 watts, so this was just some safety room for me anyway.
not really needed.
i used a wirewound resistor also, which may have caused problems.
so i dont have any complaints about the swamping "swap" but i also never got to see its effects.
the deal with the tuning was that this amp doesnt have room to mount the trimmers. (the one on the output is BIG) so i had to add one inch wires to the terminals which could have caused some problems.
again, i just didnt do it right, tried to do too much at once and it didnt work.
im still into learning anything i can about this stuff, but im going to USE the amp for awhile before i try anything else.
thanks for all the help, im learning alot.
gonna build the amp from RF parts soon.
looks cool,
matt |
Georgeodjungle
Intermediate Member
Username: Georgeodjungle
Post Number: 116
Registered: 1-2006
| | Posted on Thursday, June 08, 2006 - 12:15 pm: |
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ya 1 step at a time.
& wirewound will work.
some amps come with them.
where did you get your trimmers?
i use alot of them.
well at least ya got some amp stuff under your belt.
how big of an amp are ya gonna build? |
