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KC8FWD
12-10-2008, 01:11 AM
Does any one have any schematics for a dual 8877 amp and a power supply or a 3 3-500z amp and power supply? if so can I get a copy I would like to build a amp like these for 10 thru 160 meters using vaccuum vari capacitors and a roller inductor thanks Mike KC8FWD

KA4DPO
12-10-2008, 02:13 AM
Copy the Ameritron schematics.

WB2WIK
12-10-2008, 02:14 AM
Copy the Ameritron schematics.

::Ditto, that's a good idea. And I cannot imagine why it would be worthwhile using two 8877s, when a single one can produce 2500W output power easily.

WB2WIK/6

AC0FP
12-10-2008, 03:24 AM
::Ditto, that's a good idea. And I cannot imagine why it would be worthwhile using two 8877s, when a single one can produce 2500W output power easily.

WB2WIK/6

Nothing like a couple of 8877's to help you GET OUT! When your enjoying your 807's! :D:D

K7MH
12-10-2008, 03:38 AM
I'd prefer a six pack of 4-1000A's.:)
OK...a four pack will do.

AG3Y
12-10-2008, 04:42 PM
And you can use your amp to heat your house, at the same time !

KA4DPO
12-10-2008, 05:36 PM
I have an old Alpha 76 PA that has a pair of 8866's in it. It will run about 1.8 to 2KW out the tailpipe (that's CB talk for throwing watts) with ease.

I havent used it in quite some time so when I do decide to take it out of mothballs it will take a while to bring it back up without damaging the tubes.

Once I get moved I plan on selling it and getting an AL-80B. I'm convinced that anything over a KW is a waste of power. From what I've read, you can get a reliable 700 watts out of an AL-80B. Thats good enough for me.

WA2ZDY
12-10-2008, 10:02 PM
It will run about 1.8 to 2KW out the tailpipe (that's CB talk for throwing watts) with ease.


Something tells me that statement may have extra relevance.

W8JI
12-11-2008, 12:22 AM
I have an old Alpha 76 PA that has a pair of 8866's in it. It will run about 1.8 to 2KW out the tailpipe (that's CB talk for throwing watts) with ease.



"Throwing watts" , what the heck does that mean? Is it like throwing up?

What is an 8866?? How did you fit it in an Alpha? Was it an 8874 code date 8866, or an 8866 code date 8874.

"I can't make my mind up whether to run 1000 watts of dissipation or 3000 watts of dissipation." I can't make up my mind whether to have a glass of sour milk straight or with two scoops of dirt.

What the heck? Is this the twilight zone? Am I confused? How much wood could a wood chuck chuck?

Help.

KA4DPO
12-11-2008, 12:47 AM
"Throwing watts" , what the heck does that mean? Is it like throwing up?

What is an 8866?? How did you fit it in an Alpha? Was it an 8874 code date 8866, or an 8866 code date 8874.

"I can't make my mind up whether to run 1000 watts of dissipation or 3000 watts of dissipation." I can't make up my mind whether to have a glass of sour milk straight or with two scoops of dirt.

What the heck? Is this the twilight zone? Am I confused? How much wood could a wood chuck chuck?

Help.


Just trying to be clever. Actually I do have a 76PA but it has 8877's in it. I heered them 8866's was special from a gud buddy somwhere along the line.

And no ZDY, I would rather drink draino than listen to the vermine on 27 MHZ. That stuff has never happened at this QTH and never will...

WB2WIK
12-11-2008, 02:08 AM
Just trying to be clever. Actually I do have a 76PA but it has 8877's in it. I heered them 8866's was special from a gud buddy somwhere along the line.



::How'd you fit 8877s in a 76PA? The 76PA used 8874s, which are about 1/3 the size of 8877s...that would be a really interesting conversion.

WB2WIK/6

WA2ZDY
12-11-2008, 02:24 AM
And no ZDY, I would rather drink draino than listen to the vermine on 27 MHZ. That stuff has never happened at this QTH and never will...

My apologies for not being clear. I didn't mean at YOUR QTH - it wasn't you asking how run a pair of 8877s.

AD5ND
12-11-2008, 03:05 AM
Comment deleted by Me, Myself and I. Because of unfriendly content about people who run MEGA power.

WA9SVD
12-11-2008, 03:19 AM
I have an old Alpha 76 PA that has a pair of 8866's in it. It will run about 1.8 to 2KW out the tailpipe (that's CB talk for throwing watts) with ease.

I havent used it in quite some time so when I do decide to take it out of mothballs it will take a while to bring it back up without damaging the tubes.

Once I get moved I plan on selling it and getting an AL-80B. I'm convinced that anything over a KW is a waste of power. From what I've read, you can get a reliable 700 watts out of an AL-80B. Thats good enough for me.

How are you going to convince any respectable CB'er or freebander to buy such a wimpy low powered amp, unless they are going to use it as a driver for their REAL amp?:rolleyes:

(OK, satire/Sarcasm off.)

W8JI
12-11-2008, 07:21 AM
::How'd you fit 8877s in a 76PA? The 76PA used 8874s, which are about 1/3 the size of 8877s...that would be a really interesting conversion.

WB2WIK/6

I put 3-500Z's in my FL2100.

I used a backhoe.

KM5FL
12-11-2008, 08:01 AM
I put 3-500Z's in my FL2100.

I used a backhoe.

That's nothing.... I put 4-1000s in mine... Used a back hoe and TWO road graders in push-pull.. :p :p


KM5FL

W2VW
12-11-2008, 01:39 PM
I put 3-500Z's in my FL2100.

I used a backhoe.


Oh yeah. I have a YC-156 in my Heath Warrior.

WB2WIK
12-11-2008, 04:18 PM
I put 3-500Z's in my FL2100.

I used a backhoe.

::The hoe was where?:p

KA4DPO
12-11-2008, 04:47 PM
::How'd you fit 8877s in a 76PA? The 76PA used 8874s, which are about 1/3 the size of 8877s...that would be a really interesting conversion.

WB2WIK/6

The guy I bought from in Georgia changed the deck way back in 1980. I got it at the Augusta hamfest for 900 dollars and I was pretty sure at the time it was a CB hack but the price was right and he did demo it. It also was done very nicely from a mechanical standpoint and doesn't look like a cardboard cutout. Also, the power supply was upgraded from 2600 to 3800 volts. Regardless, it's a workhorse and runs pretty cool even at 400 watts carrier on 75 meter AM.

WB2WIK
12-11-2008, 06:13 PM
The guy I bought from in Georgia changed the deck way back in 1980. I got it at the Augusta hamfest for 900 dollars and I was pretty sure at the time it was a CB hack but the price was right and he did demo it. It also was done very nicely from a mechanical standpoint and doesn't look like a cardboard cutout. Also, the power supply was upgraded from 2600 to 3800 volts. Regardless, it's a workhorse and runs pretty cool even at 400 watts carrier on 75 meter AM.

::And that was a 76PA? Any photos of this conversion?

The 76A, which is the same but used three 8874 tubes instead of two (same chassis, though, same power supply, etc), has a tube chassis measuring 4.3 x 6.8" overall as shown in the photo attachment. An 8877 is 3.365" in diameter. Placing two of them side by side, diagonally or any other way into the available space, even if they touched each other, would be impossible without one of them shorting against the rear panel. Seems like an "impossible" conversion without a new chassis, new cover...relocating everything inside the amp...

Sure that's a 76PA? The 77SX was available as a standard model with two 8877s, no conversion required, but it's twice the size.

WB2WIK/6

KA4DPO
12-11-2008, 06:32 PM
::And that was a 76PA? Any photos of this conversion?

The 76A, which is the same but used three 8874 tubes instead of two (same chassis, though, same power supply, etc), has a tube chassis measuring 4.3 x 6.8" overall as shown in the photo attachment. An 8877 is 3.365" in diameter. Placing two of them side by side, diagonally or any other way into the available space, even if they touched each other, would be impossible without one of them shorting against the rear panel. Seems like an "impossible" conversion without a new chassis, new cover...relocating everything inside the amp...

Sure that's a 76PA? The 77SX was available as a standard model with two 8877s, no conversion required, but it's twice the size.

WB2WIK/6

When I dig that anchor out of the basement I'll post a photo of the deck. It's a clever arrangement and it does fit.