SSB Carrier Supression

[Mikebits]

Thats seems a bit drastic. How about ya arm wrestle instead?

 

[Space Varmint]

He's free to come over here for a fight if he wants?

Marquis Queensbury rules?

 

[flat5]

Marquis Queensbury sounds gay

 

[Nigel Goodwin]

Marquis Queensbury rules?

Certainly not! - FAR too restricting

 

[Space Varmint]

Certainly not! - FAR too restricting

Oh, your a street fighter....OK

 

[Space Varmint]

That Nigel is a scary fellow ain't he?

Well got the PLL/VXO working pretty good. Put a couple of extra switches in the schematic to activate a couple of port bits. This will enable me to leisurely jump into other modes like divide by 11 or 12 or 9 even to where I can probably get pretty close to 1KHz resolution effectively, or performance wise, while it is still doing the higher resolution for filtering purposes. I may eventually, be able to dump the variable cap in the VXO circuit, although it will always come in handy for the convenience of shifting the tone a few hertz for the receiving station. I would say, as it stands right now, judging by ear, I have greater than 60db down on the phase sidebands.

 

[xanadunow]

Just trying..

OK, Here's a picture of the world's smallest 80 watter

SV.. This thing looks like a dissaster zone from Gaza. To expect any reasonable results you do need to "clean up" your technique.. I won't go to lenghts - but just look in the very centre of your picture.. see the 520Ω? resistor there accross the RF transistor? If this is not a dry joint .. I'll shut up. You do have "blobbes" of solder and a lot of flux all over the place.. (btw- that resistor looks like it has been attacked with a chisel).

If there are to be any comparable results you'e looking for dear SV, every "project" must be "neat" to be consitant with your tests. This is even more so when in RF designs.

It is only suggestion of mine that you throw this "thing" into a bucket, poure a litre of methylated spiryt (and set it alight..) .. No!!!

No - joking.. pour the metho in and let it seat the for 3 days. Then, as you're taking it away, brush off all the flux away (it should have resolved all but some by then).

Then with a good magnifying glass, take some crticism of yourself and "re-do" the joints that (surely), even to you do not look right..

[I do pride myself on the best soldering joints there are and I did fail my own tests under the microscope more times than I can even remember]

Microscope is not reqired but a good x 15to20 watchmakers glass will tell you more than I can say..

Only after rectifying these joints you do not like yourself, you will have the RF AMP "worthy" sharing your comperative experiences with.

Also, if you do want to improve your design.. buffer, isolate supplies.. as suggested in many posts earlier.

[Think of it also along these lines; if the AMP overloads the Driver, then the driver probably overloads the Mixer..]

Most of all - if your assembly technique is not up to standard - do not expect results even if you had used 100s of PICs..

xanadunow

 

[Space Varmint]

Hey that's pretty funny Xan Now which one are you talking about? The 80 watt amp? Probably. That thing has been re-worked a few times. I used to have a T/R relay stuffed in that box as well. nI just snatched that out. But I am telling you, this sucker puts out the watts and it is clean clean clean. I mean nice! I got a TV set in this room that runs off an areal antenna. Just local broadcast, and it does not pick up the slightest interference on any channel. So right now, it is performance I'm after. Now when I get a chance, I will do exactly as you say. In fact I have some real nice Avvid heat sinks with fins that are about 4 inches stinking out from the base which is about 6 or 7 inches long and about 4 inches wide. I think I will build a push pull on it. Also I need to mount that LM317 on it too because that baby gets hot! It is basically suspended by wire because no matter what I put on it to cement it to a two watt resistor, expoxy or anything, it melts. It has even de-soldered itself before. When I first put it together I didn't have much on hand.

In fact here's a HF 80 watt amp I made using one of the Avvid heat sinks but it is class C:

 

[Nigel Goodwin]

Oh, your a street fighter....OK

Not as such, I'm a registered Ju Jitsu instructor and grading examiner (3rd degree Black Belt), and the Marquis of Queensbury rules prevent pretty well every thing we teach

Even the bare knuckles fighting the Marquis of Queensbury rules were desinged to prevent doesn't allow most of what we do.

 

[Space Varmint]

Not as such, I'm a registered Ju Jitsu instructor and grading examiner (3rd degree Black Belt), and the Marquis of Queensbury rules prevent pretty well every thing we teach

Even the bare knuckles fighting the Marquis of Queensbury rules were desinged to prevent doesn't allow most of what we do.

God dern!!!! You bad ain't ya? I'm a 10th dan in mean!

 

[Space Varmint]

Hey, did you see UFC wired last night? That dern Canadian got his belt back. That was shameful! Just shameful. He made that American boy look like baby Huey.

 

[Space Varmint]

OK, thought I disappeared on ya, didn't you? Nope, just got busy, that's all. Here's what I did. I hooked up the 80 watter and it was putting out a gorgeous signal after some re-work then I CQed & CQed (call to any station) but got no calls back. Well, at 80 watts you can only imagine what my receiver sounds like listening to my own signal. Oh, oh did talk to one guy who said my frequency was "wondering". So I constructed a PLL for it. I am in a hurry to get most of the band, so I took a short cut until I have time to update the programming. So, since I am creating the reference frequency using the PIC timer, I figured I would supply the processor with an external crystal clock and make it a VXO so I could vary the reference. I think my frequency is allot more solid now and I can actually make sense of my signal using the receiver sitting right on my desk.

Well, when I changed my signal source to PLL in my up-converter, I had to go down the chain looking at amplifiers and filters to keep the signal drive for the 80 watter. I did make some changes and I got so tired yesterday I never tried a QSO.

Here's the changes in the up-converter. The two wire cable is some RG-174U from the modulator section. The up converter puts out about 1/8th watt and is sufficient to drive my 8 watt linear amp which drives the 80 watt.

 

[flat5]

Hi SV, I like following this thread.
You really are not a fan of decoupling Vcc locally.

 

[Nigel Goodwin]

Hi SV, I like following this thread.
You really are not a fan of decoupling Vcc locally.

No, he doesn't like to build things that work

He's also got a strange darlington fetish as well (although he can't seem to draw them correctly).

 

[Space Varmint]

Hi SV, I like following this thread.
You really are not a fan of decoupling Vcc locally.

Yes I decouple quite a bit, but what do you mean by local? You mean every stage? No I don't do every stage.

To answer Nigel, yes I do have a fetish for Darlingtons because if you are needing a buffer, why not get the extra current drive, after all the bottom line is power out, so....IXE

 

[Space Varmint]

Well let's see. The saga of SSB. What's up, what's up? I had the 80 going again and I noticed I had too much image frequency. So I put another crystal in the filter and man, it is just right. Not too sharp and greatly reduced image. Sounds like everybody else. Even when I run bare foot at 8 watts, my freq counter displays my frequency when I talk.....that's sweet! Picking it up through the air.

Hook up the 80, and dambit! I press the mic key and it feedsback rf. ****! Dambit! Also got some carrier. Getting this 80 to work is hell! I think I need lot's more shielding. Probably need to re-do most of the power cables and maybe heavier boxes. Not sure. Have to get back on that.

 

[flat5]

Do you have a very good ground for the transmitter-power amp?
Low VSWR?
Antenna at some distance from the "shack"?

 

[Space Varmint]

Do you have a very good ground for the transmitter-power amp?
Low VSWR?
Antenna at some distance from the "shack"?

Hey, thanks for asking flat5. My SWR is great. About 1.1 to 1. But I have been grounding it to the boxes of the driving networks. Should I try earth ground?

 

[flat5]

yep with a big fat copper something if you can.
Just good practice with a high power transmitter.
I suppose sometimes it makes a difference whether someone can receive you or not. Anyway, it's supposed to help keep RF out of the shack. (as you know)

 

[Space Varmint]

yep with a big fat copper something if you can.
Just good practice with a high power transmitter.
I suppose sometimes it makes a difference whether someone can receive you or not. Anyway, it's supposed to help keep RF out of the shack. (as you know)

OK, I will try it. Thanks. It does make sense. Another thing too, is this mic has been modified. It has some cut wire where someone removed the VOX. It has good ground as far as the audio signal out, so not sure if I need to be concerned but like I said, right when I key down I get the rf feedback.