Driving an amp with amp?

[KE7HQY]

I currently have a Motorola NLD7702A VHF amp that puts out roughly 60 watts, however I would like to get into the hundreds of watts output. I am strictly looking at SSB/CW for modulation, so FM requirements is not an issue. Unfortunately my radio only puts out 10 watts, which is well below the needed 30-50 watt drive needed for most of these high-powered amps.

I know there's amps out there that will put out hundreds of watts with 5 watt drive, but they are prohibitively expensive for my budget. My current budget only allows for second-hand ebay/qth/qrz listings below the 250 dollar mark or so, which doesn't offer much in the way of these special amps.

So this all brings me down to the question, can I drive a secondary amp that puts out hundreds of watts with my current amp?

[N0IU]

Champagne taste on a beer budget!

[WA9SVD]

The step from your current 10 watts to the 60 Watts is marginally an improvement at best; there's little to be gained in "daisy chaining" amps in your suggested configuration, and it would be inefficient at best.
You also don't specify the actual Amateur frequency on which you are operating.
Your best option may well be homebrew for an amp that is directly driven by your present 10 Watt transmitter.

[KE7HQY]

I am operating on 2 meters.

In regards to inefficiencies, it seems to me that there wouldn't be much of a loss in signal, as the signal coming out of the amp would just be amplified. Now in regards to reception, is that effected? Please elaborate.

I am also not afraid of home brewing if that would make it work better. I don't have much if any experience reading schematics, however I can definitely solder things together and build them http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

[K7JEM]

One concern is that the amp you mention is probably intended as an FM amp, and will not work properly on SSB anyway.

[WA9SVD]

Quote[/b] (KE7HQY @ July 05 2007,23:41)]I am operating on 2 meters.

In regards to inefficiencies, it seems to me that there wouldn't be much of a loss in signal, as the signal coming out of the amp would just be amplified. Now in regards to reception, is that effected? Please elaborate.

I am also not afraid of home brewing if that would make it work better. I don't have much if any experience reading schematics, however I can definitely solder things together and build them http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif
2 Meters at least gives us some info.

The "efficiency" is in regards to using an "amp" to make a very minor gain to drive another amp. It WOULD be much more efficient to go directly from your current 10 Watts to your QRO desire of the 100's of watts, without using the Motorola amp. (Whether or not it is capable of linear operation; that's an entirely different issue for another thread.)

On the receive side, In general, at 2 Meters, there would be no significant loss or gain in signal with an outboard amp, unless it contains a receive preamp. A preamp may not hurt, but may not help either at the 2 Meter level. It may simply raise the noise level to the same amount it raises a signal, which is no real improvement overall.

At the 10 Watt level, what sort of equipment are you using for transmit and/or receive? Taht may make a difference in recommendations.

[N5RFX]

Quote[/b] (KE7HQY @ July 05 2007,00:20)]I currently have a Motorola NLD7702A VHF amp that puts out roughly 60 watts, however I would like to get into the hundreds of watts output. I am strictly looking at SSB/CW for modulation, so FM requirements is not an issue.
The NLD7702A is a class C amp. If I understand your statement (which I am not sure I do) this is not an amp for SSB work.

What do you mean by "FM requirements is not an issue"?

As far as daisy chaining amps, it is done all of the time. A driver amplifier is one that drives the power amplifier. You are going to have to build a linear amplifier to operate SSB, so as others have stated, you need to start from scratch.

73,
Mark N5RFX

[AI4IJ]

Get a Mirage B1016G amp off ebay for between $150 and $200. #It will take 10 watts in and give you 160 watts out, has a preamp, #and is also capable of SSB and FM operation. #Mine has given me good service for about two years, now.

Then, focus on antennas for real improvement in your transmitted and received signals. #You'll get more bang for the buck in an antenna than any amp - especially, if you build it yourself.

73
Richard
AI4IJ

[VE2NSM]

Quote[/b] (K7JEM @ July 06 2007,02:49)]One concern is that the amp you mention is probably intended as an FM amp, and will not work properly on SSB anyway.
That is in fact my biggest concern as well. For SSB/AM work you need a linear amplifier, it can work for FM also. On the other hand a standard "power amplifier" for FM work will give you a very distorted signal on SSB.

[WA9SVD]

Quote[/b] (ve2nsm @ July 06 2007,09:21)]
Quote[/b] (K7JEM @ July 06 2007,02:49)]One concern is that the amp you mention is probably intended as an FM amp, and will not work properly on SSB anyway.
That is in fact my biggest concern as well. For SSB/AM work you need a linear amplifier, it can work for FM also. On the other hand a standard "power amplifier" for FM work will give you a very distorted signal on SSB.
An illegal signal, not just distorted.
A Class C amp is only suitable for CW or FM. AM or SSB requires a linear amp, and that requires different biasing of the output device(s,) which is probably impractical if not near impossible with the Motorola amp. Save the Motorola for an FM mobile installation, or sell it and put the proceeds toward the appropriate type of amp.

[K9FV]

HOY, is there any way you could put up a 2 meter beam - with say a 10 ft boom? OR 14 ft> {grinning} - that could really improve your recieve as well as increase your ERP a LOT!!! With 12 db gain antenna and a single 150 watt amp, your ERP would be 2400 watts - NOT counting line loss - even with the losses, you've still have the legal limit output power - well, actually there is NO upper ERP limit on 2 meters, but you get the idea.

73 de Ken H.

[N8YX]

Look into building an amp using a 3CX800A7 or equivalent tube.

The Radio Amateur's Handbook has featured a number of low-drive VHF amplifier designs over the years; the aforementioned 3CX- variant is capable of ~700w output in AB2 when driven with 15-20w...

Obtain the 1988 edition of the Handbook. Amps for both 6 and 2 meters using this tube are listed.

[AG3Y]

Just be prepared for "sticker shock" when you see your electric bill! Especially if your electric company is doing what ours are in the good old state of Maryland! ( caps removed, What Price Ceiling ? http://www.qrz.com/iB_html/non-cgi/emoticons/rock.gif )

[KE7HQY]

Thank you all for the responses! Also, thank you for the note that my current amp only does FM.

to answer some questions:

I am looking to use this amp for low-bar EME work with my 13b2 Cushcraft 2-meter yagi and rotor. Its got roughly (EDIT:) 16dbi of gain, and with a couple hundred watts would be adequate for JT-65 software QSOs (using ground gain http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif ) I'm not going for a contest station, just for fun.

Also, I really like the looks of the 160 watt mirage amp, especially since it does both FM/SSB. I can switch between the two and only have one amp to deal with.

However I am also mulling over home brewing the entire thing, as that way I can get the 700-1000 watts out of it without spending mucho $$$ on the large-wattage commercial amps.

However just doing a quick search on the 3CX800A7 tube prices indicates they are still extraordinarily pricey comparatively.

I've been doing a bit of searching around for other homebrew 2meter amps, and came across something called the "Homebrew 8877", which supposedly puts out about 1500w. The 8877 tubes seem to be a bit less expensive. However they also require a drive of about 65watts, which would require another amp.

My question for this is, would it be possible to drive a homebrew amp with the mirage linear? Budget allowing, I could set the homebrew amp for a longterm project and just buy the mirage and do basic EME with it until I can get the hombrew amp to work.

[WA9SVD]

Quote[/b] (n8yx @ July 06 2007,11:51)]Look into building an amp using a 3CX800A7 or equivalent tube.

The Radio Amateur's Handbook has featured a number of low-drive VHF amplifier designs over the years; the aforementioned 3CX- variant is capable of ~700w output in AB2 when driven with 15-20w...

Obtain the 1988 edition of the Handbook. Amps for both 6 and 2 meters using this tube are listed.
A 3CX800 is going to require more than 10 Watts drive!
The 6 M amp in the 1991 HB (I don't have the 1988 HB with me) requires 25 Watts drive, 2 Meter versions usually require more drive; possibly as much as 50 Watts, according to the 1991 HB. (Page 31-35.) Various designs in the HB's using external anode triodes on 2 M require from 19-50 watts, which is more than our friend has available.

For low drive you would need something like a Tetrode vacuum tube. Something like the 4CX250 series could give you something like 300 Watts output, and only require a few watts drive, mostly loss in the input circuit. The 1991 HB has such a project, as well as a circuit using a 4CX1000A, which requires about 10 Watts drive on 2 Meters, with 2 KW input, it has roughly 1200-1400 Watts output.

[W2VW]

Build a W6PO amp but use a GS-35B to save bux. Find a way to reduce drive to the brick amp when using the tube final. You could even cut in 100 feet of RG-58 in the T/R circuit to lose some drive. That throws headroom away though.

[KA0GKT]

It is fairly common to use one amplifier to drive another. Some legal limit VHF amplifiers require more drive than some of the older all-mode transceivers were capable of providing, In these cases an amplifier was used in advance of the final amplifier. This is also quite common in broadcast transmitters. In the commercial world, the term IPA (Intermediate Power Amplifier) is used for these amplifiers. The venerable McMartin BF-5K 5-KW FM amplifier cabinet has a Grounded-Grid final driven by a pair of 4CX250B tubes parallel in the IPA. The IPA amplifies the 10-Watt (nom.) power output from the FM exciter. The Harris TV-30L which I maintain takes the nominal 1-watt output from the visual exciter, boosts it to 80-watts (Peak Sync) in a solid state IPA, then to 800-watts (peak sync) in a driver tube and then to the full 30-KW (Peak Sync) in the final amplifier; so, in this case, there are two amplifiers before the final amplifier.

Good Luck.

73 DE KAØGKT/7

--Steve

[WA9SVD]

Quote[/b] (KE7HQY @ July 06 2007,18:39)]My question for this is, would it be possible to drive a homebrew amp with the mirage linear? Budget allowing, I could set the homebrew amp for a longterm project and just buy the mirage and do basic EME with it until I can get the hombrew amp to work.
Certainly, you could use the Mirage amp to drive a higher powered amp. And running the Mirage at reduced power out would make it produce a cleaner signal than if run full power.
But again, daisy chaining in this way is an inefficient and expensive way to go about things.

[W2VW]

The only amplifiers that will take a 10 watt signal to legal limit are tetrode or XXXX+ode amplifiers. Since the poster is interested in linear operation, the idea of using one of these isn't all it's cracked up to be. CW or FM would be a different story. Tetrodes require a lot of support circuitry in order to deliver a good clean signal. Even then most circuits will not behave as well as popular triodes in simpler designs. Tetrodes need a low inductance screen bypass capacitor, regulated screen supply capable of sinking negative screen current and handling occasional internal tube arc over without launching itself and some type of R.F. feedback in order to approach IMD of cathode driven triode. Put it on a balance sheet. Put the extra stage driving triode amp on the other side of the balance sheet. Of course the poster will need a stout 12 volt power supply to run a 160 watt brick.
One dollar wise solution would be to get a 100 watt radio.
I'd much rather see this person build something even if it isn't the most efficient of all choices. Efficiency and resonance are over rated IMHO.

http://www.landfall.net/Radio/8877-1.htm

[WA9SVD]

Quote[/b] (w2vw @ July 08 2007,07:24)]The only amplifiers that will take a 10 watt signal to legal limit are tetrode or XXXX+ode amplifiers. Since the poster is interested in linear operation, the idea of using one of these isn't all it's cracked up to be. CW or FM would be a different story. Tetrodes require a lot of support circuitry in order to deliver a good clean signal. Even then most circuits will not behave as well as popular triodes in simpler designs. Tetrodes need a low inductance screen bypass capacitor, regulated screen supply capable of sinking negative screen current and handling occasional internal tube arc over without launching itself and some type of R.F. feedback in order to approach IMD of cathode driven triode. Put it on a balance sheet. Put the extra stage driving triode amp on the other side of the balance sheet. Of course the poster will need a stout 12 volt power supply to run a 160 watt brick.
One dollar wise solution would be to get a 100 watt radio.
I'd much rather see this person build something even if it isn't the most efficient of all choices. Efficiency and resonance are over rated IMHO.

http://www.landfall.net/Radio/8877-1.htm
It all depends upon the design; certainly, a tetrode amp requires a bit more control circuitry, but none of your points are insurmountabler obstacles, they are handled by good design. An adequate screen supply is hardly much more difficult than a supply for any other voltage or current capability, that's really not a valid objection. Is the cost of a screen supply and bias supply really the equivalent of an amp such as the Mirage and an Astron RS-50 Power supply? IMHO, not even close.
A poorly designed (or poorly executed) triode amp can be just as unruly as any tetrode amp. Again, proper design is the key, as well as understanding the PROPER use and operation of an amp. regardless of the active devices used.

[WA9SVD]

One question here begs to be asked, but hasn't been addressed:

HQY wants to do EME. With 160 Watts and a modest, very modest, (by EME standards) antenna; a single Yagi.

Let's put things into perspective, and above all, NOT put the cart before the (dead) horse.

Will such a setup REALLY work for SSB EME contacts?

HQY:

I would ask:

1. Do you already have the antenna system worked out, with the rotators for azimuth and elevation? Are the controls calibrated and working properly?

2. Do you have very low loss feedline going to your antenna?

3. What type of mast-mounted preamp are you using?

4. Have you asked some of the "Big Gun" EME folk for some of their skeds so you can test your receive set up? It might be considered rude to ask them to set up a oneway sked just for you, but most will not mind if you attempt to listen in on their ongoing schedules.

5. DO you have a low noise receiver? What equipment are you using?
.
6. Have you reviewed the literature on EME and calculated your pathloss both ways for EME work?


Until you have a setup where you can actually HEAR EME signals, all the talk in the world about transmitter power, etc. is futile. If you can't hear them, you can't work them, regardless of how much power you run. And running more transmit ERP power than can be matched by your receive capability is considered rude and a poor, very poor, operating practice.

Once you get your receive capability sufficient, THEN worry about increasing tramsmit power.

[W2VW]

Quote[/b] (wa9svd @ July 08 2007,08:20)]none of your points are insurmountabler obstacles, they are handled by good design. An adequate screen supply is hardly much more difficult than a supply for any other voltage or current capability, that's really not a valid objection. Is the cost of a screen supply and bias supply really the equivalent of an amp such as the Mirage and an Astron RS-50 Power supply? IMHO, not even close.
A poorly designed (or poorly executed) triode amp can be just as unruly as any tetrode amp. Again, proper design is the key, as well as understanding the PROPER use and operation of an amp. regardless of the active devices used.
Post a link to what you consider an adequate screen supply for a 144 meg QRO amp using a tetrode or 2 and we can take it from there. Please don't forget the special screen bypass and arc over protection. Thanks.
We are assuming ruly designs of course. Apples and oranges just confuse the issue.
BTW last (4) 160 2 metre amps bench tested here fine with Astron 35 ampere supply. 50 is nice but adds no efficiency.

[WA9SVD]

Well for starters, tubes such as the 4CX250 are designed to be used with a low inductance screen bypass ring, that's designed and functions at least to the frequency limits of the tube. If it works well to 500 MHz, it should be fine at 2 Meters. A pair of 4CX250's should do 6-700 watts out quite nicely.

Since you were quoting ARRL Handbook projects, here goes:

1. 1991 HB. A 2 KW PEP Amp for 50-54 MHz. 10 Watts drive produces 2 KW input, 1200-1400 Watts output. The tube socket for the 4CX1000A includes an integral low inductance screen bypass capacitor. The screen supply is current limited to prevent excess screen dissipation.
Pages 31-35 - 31-38.
( A 2 Meter amp could use the same screen protection system.)

2. A medium Power 144 MHz Amp. 10 Watts in, 300 Out with a 4CX250R or equivalent. Granted, not the KW level,
The screen is protected with a Zener regulator and bleeder, with a MOV to protect against overload. Again, the same design cal be used for any tetrode by changing the Zener string to the appropriate voltage.
1991 HB, Pages 31-39 - 31-45.

3. A legal Limit 2 Meter Tetrode Amplifier. 10 Watts using either a 4CX1000A or 4CX1500B (interchangeable in this application) produces legal limit of 1500 Watts.
This design directly grounds the screen (eliminating any "bypass" problems) and floats the cathode. Still, 40dB isolation was measured between input and output. The design uses the same protection scheme used in the medium power amp cited above.
1991 HB pages 31-57 - 31-72

So, there are three examples just from a single edition of the ARRL Handbook.

The truth is that grounded grid designs with triodes CAN be much more forgiving of sloppy design or construction. (Even the best design, GG triode OR grid driven tetrode can be ruined by sloppy construction.)

[WA7KKP]

I'd homebrew a 4CX250 amplifier -- one or two will drive nicely with your exciter, and they are quite common and cheap (common IPA stage in (broadcast) FM transmitters).

Yes amps can be cascaded, but when you only need 3-6 db power gain, it is a waste of money. Just get or design something that doesn't need that IPA.

Gary WA7KKP

[W2VW]

Sri no 91 Hb hr. I will make it a point to find one. Thanks for the idea. Your description is good enough to get me into trouble. Grounded screen is a wonderful thing. I have a Harris HFL-1000 and 30S-1 so am familiar with the concept. Ever talk with someone who homebrewed a grounded screen amp? If so you have me beat. Homebrewers run away when they figure that screen supply needs to be able to supply plate current (which it doesn't). Back to common cathode. Add up price tag for all components to build the screen supply that you don't need with a triode and an expensive socket with built-in screen bypass. That gets one pretty close to a second hand IPA in my book. Also I'd avoid any tube like a 4CX1000 or 1500B as collectors drive the price up for 30S-1s. Grid dissipation is very unforgiving in order to provide intercept point for reasonable IMD. Call in the communist tubes like GU-84 or 78.
GS-35B triode can be had every day new for under $150.00. It needs no socket at all. Simple voltage doubler plate supply with 3200 volts and the chimney can be a piece of orange turbocharger hose.

[WA9SVD]

VW:

There are advantages and disadvantages to both philosophies. Triodes ARE usually somewhat more stable, because of their lower gain. Tetrodes, on the other hand, have low drive as an advantage, if that is what is needed, and either type of tube can be made to work; much of it is a matter of where you want to put the resources; into a properly designed amp with low power drive requirements, or into a properly designed GG amp and a commercial IPA.
It's not impossible to build tetrode amps that are stable and just as easy to use as triode amps. The K2RIW amps were also quite good and stable for their time, using 2-3 4CX250's. Not legal limit any more, but still a respectable signal level.

The real reason (IMHO, of course) triode amps have been so prevelant is two, perhaps three fold.

1. I'll agree, they may well be more forgiving of misuse, if not abject abuse.

2. Most transmittere/transceivers since even 1978 have had power output in the 100 Watt or more category, enough to drive a lower gain amp to QRO status..

3. The high (usually 55-70 watts, sometimes more) drive power necessary to achieve legal limit (or any QRO power level) required by the FCC regulations. QST was loathe to publish designs for low drive amps, especially for HF amps, that could be "stolen" and used as plans for CB frequencies. (Prior to '78, they DID publish plans for HF amps using the 4CX250's; a 2E26, 5763, or even a 6CL6 was often enough to drive them to the full 1 KW power input allowed at the time.

I'll be curious to know what sort of equipment HQY is using with only 10 Watts power output.

And I'll have to take a look at the Russian tube offerings.

[K8JD]

I only saw a brief reference to antennas in the replies. At the power levels being discussed, the problem becomes hearing any replies to your calls! If you put your resources into antennas and low noise receiving pre-amps you would have a more even match, transmitting and receiving. Its no fun being an aligator with all mouthl and no ears!

[KE7HQY]

Looking at all the responses (thank you!), it seems I really need to up my receiving capability. I'm going to build a second yagi to stack onto the Cushcraft and hopefully that will get some better gain out of the setup. I'm also planning on getting a GaAsFET preamp and putting it at the antenna to increase reception.

I am primarily looking at pointing the yagis at the horizon, as that gives me maximum ground gain. However, would it be possible with 1KW and ~18-19dbi gain to make it without ground gain aid? EDIT: I overestimated the gain of the single yagi in my first post earlier. it only gets about 16dbi. Stacking should give it the above 18-19dbi or so.

I am using a IC-706 original as my main rig. I have been using it mainly for HF work, and I've figured it would be cheaper to get a linear brick than to upgrade to IC-706IIG, which is $750 when I got this rig for $400.

In response to wa9svd, I am not planning on doing EME SSB, which is very difficult with this setup. The reason I included SSB in my original post was I also want to use my setup to also do 2 meter troposcatter. I'm looking at strictly CW/Software modes (JT-65,etc). Also, upon contemplation of what you were saying about seeing what I can hear first makes perfect sense. I'll build the entire setup, antennas, preamp, low-loss cable, etc. and then worry about the amp as the last. I.E. decode as much EME as possible before broadcasting it.

I have a I just realized that the electrical circuit my radio on has a 20 amp 117v AC circuit breaker on it, which also has a window air conditioner on it! But looking at the efficiencies of the W6PO for reference, I could probably do a 1KW output setup no problem, as that draws 1500 watts and my air conditioner can probably still run with that.

I also just bought a wall-wart wattmeter and will check what kinds of draw the air conditioner and other things are doing. It should be here Wednesday, so I'll have a better estimate of what I can do then.

[AG3Y]

If you are planning to run a kilowatt amplifier, you really want to wire the shack for 220v ! Especially if you are running a window AC unit anywhere near the same circuitry!.

This link: http://www.g8wrb.org/data/Eimac/4CX250B.pdf shows a plate dissipation of 250 watts, and I would certainly NOT recommend trying to get more than 500 watts out of a pair of these tubes in any mode!

Good luck with your project. 73, Jim

[KE7HQY]

I may look into rewiring the circuit, however I am not too sure if that would be feasible considering my house layout. I'll definitely need to check into it though, as I think you're right that getting its own circuit would help make sure everything runs smoothly.

In regards to tubes, I am really looking at the GS- russian tubes from Svetlana. They seem to be fairly cheap and are fairly reliable from what I've read.

[WA9SVD]

Quote[/b] (k8jd @ July 08 2007,18:13)]I only saw a brief reference to antennas in the replies. At the power levels being discussed, the problem becomes hearing any replies to your calls! If you put your resources into antennas and low noise receiving pre-amps you would have a more even match, transmitting and receiving. Its no fun being an aligator with all mouthl and no ears!
That was my point above. You have to be able to HEAR the other stations before you can even think of working them.

[WA9SVD]

Quote[/b] (AG3Y @ July 08 2007,20:38)]If you are planning to run a kilowatt amplifier, you really want to wire the shack for 220v ! Especially if you are running a window AC unit anywhere near the same circuitry!.

This link: http://www.g8wrb.org/data/Eimac/4CX250B.pdf shows a plate dissipation of 250 watts, and I would certainly NOT recommend trying to get more than 500 watts out of a pair of these tubes in any mode!

Good luck with your project. 73, Jim
The 4CX250B (and similar) are rated 250 Watts dissipation, or 500 Watts for a pair. Input can be 1000 watts for a pair, and some of the amp gurus here indicate they CAN be pushed a bit more than that, with sufficient cooling. But even with 1 kW in, you should be able to get 600-700 Watts out; 650 isn't uncommon for Class AB2, and 700 Watts isn't unusual for CW Class C. True, it's not legal limit any more, but it's still a respectable signal.

[W2VW]

Here is an excellent treatise on the subject of tetrodes and how to make them work in ham service. Better late than never.

http://www.muenster.de/~dl5qe/qexartic.pdf

[KE7HQY]

V2VW - thank you for the link. Good information there http://www.qrz.com/iB_html/non-cgi/emoticons/smile.gif

I'm still working on my antenna setup first to get that in place. However, I can get all the help I can in learning about Amps (which a lot of material has been already noted above). I hopefully will have a working one by the end of the summer. I'll definitely update this thread on what I do

[W2VW]

Quote[/b] (KE7HQY @ July 20 2007,18:55)]V2VW - thank you for the link.
Glad you liked it. Thanks for the relocation to Antigua. I could use a vacation. http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif

[WA9SVD]

Quote[/b] (w2vw @ July 21 2007,07:35)]
Quote[/b] (KE7HQY @ July 20 2007,18:55)]V2VW - thank you for the link.
Glad you liked it. Thanks for the relocation to Antigua. I could use a vacation. http://www.qrz.com/iB_html/non-cgi/emoticons/cool.gif
VW:

Welcome back from that vacation! http://www.qrz.com/iB_html/non-cgi/emoticons/laugh.gif

Excellent article. I've seen (and printed out) similar articles, but not that particular one. Thanks.

[WR8Y]

Quote[/b] (KE7HQY @ July 05 2007,19:39)]I am looking to use this amp for low-bar EME work ...

However I am also mulling over home brewing the entire thing...
COOL! I'v been ham since 1974 and FINALLY I am going to try EME on 2 as well. I will start off somewhat like you, a good 2-4 wavelength yagi, 40-100 watts, good preamp and pursue weak signal stuff while I am building a good array and amplifier.

My goal is to take my TS830 as an IF radio and homebrew everything else except the tower and az-el rotator. (Probably won't build my own feedline, either!)

Oh, one more thing, my transverter will be a converted commercial FM mobile radio! (Watch for my eham or QST article in about 18 months!) I have the LO and Receiver converter already done!

See you on two from Central Georiga!

73,
Mark
WR8Y