We were cluttering up the net thread, so I'm starting this for discussion about the Mercury IIIs Amplifier kit.

I will update with more pics and info when I'm home later tonight.

Edit: a little about the Mercury IIIs mostly a copy paste from the users manual.
1200 watts SSB/CW
700 watts DIGI mode

The final power transistor is a LDMOS device explained below;
The mercury IIIs uses the BLF189XRA from Ampleon USA Inc
LDMOS (laterally diffused metal oxide semiconductor) transistors are used in
microwave/RF power amplifiers. These transistors are often fabricated on p/p+ silicon
epitaxial layers. The fabrication of LDMOS devices mostly involves various ion-
implantation and subsequent annealing cycles. As an example, the drift region of this
power MOSFET is fabricated using up to three ion implantation sequences in order to
achieve the appropriate doping profile needed to withstand high electric fields.
• Silicon-based LDMOS FETs are widely used in RF power amplifiers for base-stations
as the requirement is for high output power with a corresponding drain to source
breakdown voltage usually above 60 volts. Compared to other devices such as GaAs
FETs they show a lower maximum power gain frequency.


The kit comes with with your call sign loaded in the software, I have mine blacked out in the top right corner.
The user interface is the touch screen in the picture and nice quality mechanical push button switches for power and operate.

The kit comes extremely well packaged.

Laying all the parts out.



Starting assembly, a decent 100+watt soldering iron really helps.  All the coax that requires soldering is high quality teflon insulated so there is almost no worry of melting the insulation.



Starting to get some wires hooked up.

The low pass filter board comes pre-assembled.



Low pass filter board RF shield.



90% finished with controller in place and wires routed.

Clutter. It's what I do best.

Tagging for interest.

I've ran many Amps in Car Stereo setups (have two in play right now) and several home audio amps, so I think it only natural I'm interested in Amateur Radio Amps...

One question I have and its gonna sound dumb, so be it.

These amps only amplify the transmit signal from the Radio output to the Antenna input, right?
They don't pull in the signal from the Antenna and then amplify it to your radios receive right?

Seems like if someone were far enough away to where you really needed an amp to get to them, then you'd have trouble picking them up as well, unless they too had a similar sized amp.

I know from working in the cable industry for years there is a such thing as a return or reverse amp....

I'm always curious.

Quick google re: the "receive amp" question above.



http://www.mtmscientific.com/preamp.html

Terrain can have a lot to do with pushing low wattage <100 watts.

The sun also has a lot to do with it.

I am tired of being stepped on all the time in a DX pile-up. 100w isn't doing it for me anymore.

I ordered a Mercury III last weekend.

I will do the build thread here or a stand alone thread. I was given an estimated 2-3 month ship time.

Pictures added.

This amp is feeding a non-resonant, twin lead fed doublet @ 28 feet.  The twin lead is 14ga 450ohm window line and the antenna is 13ga insulated wire from wireman.

The tuner is the Ameritron ATR-30, its a beast and will tune my doublet from 160 meters up through 10 meters allowing 1KW + operation.

The radio is a IC7300.

Any questions, ask away and I'll do my best to answer.

It looks a lot easier than I expected.

Now I am getting excited.

Thank you for posting this.

It's a fabulous amplifier and a smoking deal at the price they want for it. I would have bought one long ago if only it had featured some way to remotely operate it. Anyone who buys one will no doubt be very happy.

Instead I blew big bucks on a KPA1500

Outstanding!!!  QRO for the win!

The instructions were very good and easy to follow.  
Definitely get a 100+watt soldering iron so you don't have to hold heat on parts for to long.

I have a 700w one.

Anyone have a photo of soldering the male coax connectors onto the back panel?

I don't have a pic of that step. It is reallyy easy though.

I'm on the waiting list.

I'm on the list as well, expected delivery late Feb. Sounds like they are busy.

This may take awhile but it is in the works.

How reliable is the amp?

I was looking at buying the  dual LDMOS amp from RFKITS. They have a messafe board that used to prescribe to and those guys have those transistors blow constantly.

It concerned me because those transistors are supposed to be bomb proof and the guys witht he RF kits have to send them in to the guy in CA to get them fixed because the finals get blown all the time.

Some speculate it's because the heat sinks are sub par and have modded the PA board and fans for better heat dissipation but i don't know how those are working.

I ended up buying a 6 month old used ALS-1306 from a local ham instead for a great price.

I would ask the price, but instead will google it.

I haven't had any issues yet and the eham reviews are all 5 stars.  I run 900-1100 watts SSB and 500-600 watts digital, so about 10-20% down from the max limits of 1300watts SSB and 700watts digital.  The temp will start to raise in digital, but the fans go to high and it stabilizes.  The final has a large 1/2" copper heat spreader that should help move heat away from the device.  This kit is $2500.

Having just looked at the price, watched the video, and went to his WRZ page.



WOW!

That amp with the tuner is awesome, all touch screen and digital.

The thing I really don't like about the ALS-1306 is the analog meters.

Now I really want one.

This hobby is worse that black rifle disease. LOL


I don't see any pics of the power supply, is it separate or is it all in the same box?

Is this a cat E amp?

How long did it take you to assemble?

In SSB how loud are the fans? The ALS-1306 is pretty loud, I had to move the power supply away from the table with the mic to reduce the background noise the mic was picking up.

Just to clarify a few things. The RFKit failures were mostly back in the days of the RF2K+ kit version. The RFKit offered now is the RF2K-S which is not a kit and uses 2 LDMOS devices. Most failures were related to over driving the amp, which is why it was redesigned. The Mercury uses BLF189XRA and the RFKit uses BLF189XRB devices.

Both are excellent amps. If I was going to compare the 2 based solely an amplifier, I would say Mercury is a 1KW amp and RFKit is a 1500KW amp. Both of which have the ability to reach their rated outputs before hitting what is know as the 1 Db compression point. They both have enough headroom to prevent compression at rated output.

Both amps do come with their own built in power supply.

Compared to the MFJ (Ameritron) SS amps these are Cadillacs.

I kept reading assembly time was 5 hours or a bit more.



This is cool.   A powerful and sounds like a good design, great company and doable for a novice ham.  


I was looking at Alphas (svetlana big tubes iirc ) and Acoms.   Didn’t want to spend that kind of coin.

It is my understanding that there was no redesign from the kit to the assembled amp. It was either kit form and once it was FCC approved it came as a complete amp.

The folks in the RFkits forum specifically say they were not over driving the amp.

I read the design change was in a -2 version that also was released in kit form before it was FCC approved

What were the design changes?

Heat dissipation, or the lack there of can kill anything. RFKits says it's a 2kw amp.

ETA: I sent an email to DX Engineering and asked why them dropped the RFkits amp, but never got a response. Now the sole distributor in the US is a ham in CA running a single person business selling and servicing those amps.

Not going to clutter this thread.
Naturally everyone is going say wasn't over driving. Major problem was with hot switching especially with Icom 7300 rf tail when in qsk mode.

So the designers went back to the drawing board and changed rf switching from relay to pin diode.  They also changed from using BLF189XRA devices to BLF189XRB. The pair are rated over 3400 watts dissipation.  There was also a controller change plus software update. Believe there was an update to the LPF board. Groups.io would be the place to ask. They have a section dedicated to RF2K-S model. Check the subgroups.

Thanks,

yeah i used to belong to that group when i was looking at buying one.

Didn't know the changes were that extensive.

back to the thread,

I think i am going to look at getting one of these Mercury kits

Is it this kind of soldering? (Cup)

The new BURST 1000 and Burst 2000 should have a remote control capabilities. I just talked o a guy who bought one. He likes it a lot. Finals are water cooled.

How much are they? I tried to find a price, but couldn't.

Wow, the BURST-2000A looks very nice, very well thought out! Wish I had known about it before paying big bucks for the Elecraft, I might have taken a chance on a Russian import amp.

A little Google'ing finds a price of $4000USD which is a great deal.

Do you know if T/R switching is solid state (pin diode)? I can't tell from the website (https://bursthf.com/)

Water cooling is a show stopper for me. That shit will eventually leak all over the place

well it is named Burst.

That chart of amps posted in its own thread had it listed.

You can always use HP Imaging Oil as the fluid. It is a formulated type of mineral oil that is safe to use with electronics. You could essentially place the whole PA in a tub of it and power it up and it would be fine.

People run submerged gaming PCs in the stuff inside aquariums.

Insert Chernobyl joke here

I have a water-cooled PC. No problems at all.

It's not cup soldering.  I don't know the correct name for the type of solder joint.  Basically the connector passes through the board and you solder it where it passes through.

I'm studying up on soldering. Still don't know if I'll get one of these kits, but the soldering info is good to know, regardless.

When a component passes through a printed circuit board that's known as "through hole" construction or soldering. There's like a billion videos on Youtube on how to do that and literally every other kind of solder assembly technique. In fact I just watched a few videos on jewelry silver soldering because a cousin asked me to repair a ring she had that was too cheap for the local jewelers to want to bother with. And my silver solder paste showed up with Amazon today, so I'll be trying that very soon

Are you guys using some sort of solvent to wipe down the parts before soldering? If so, what? Acetone? Are you also putting flux on things prior to soldering? If so, what kind? I know I don't want an acid flux for electronics.

I wiped the solder points down with alcohol.  I didn't use any flux, just rosen core electronics solder.

Lot's of people do end up getting leaks.

It is just one more thing that can fail, and with very bad results.

I just don't see the reason why an amp needs water cooling, air does just fine, and dissipating 1500 watts at even the worse efficiency of the PA is not a lot, amps have been doing it just fine for many decades with just air.

To each their own, but that will be something I will avoid if possible

I use rosen core solder.

I have never wiped anything down, not even when I was building RF probes around test tubes to go into the super conducting magnet when gathering the body fluid dipole data when I was on the R&D team getting the first MRI to work in 1982

What you mean is that you don't use any separate flux, since the rosin core solder incorporates the flux in the form of the rosin (note spelling ).

Unless there is some sort of corrosion present, cleaning is not required, that is the job of the flux.

Flux is your friend. You are almost always better off with a bottle of flux with needle applicator top and regular solder. Cleaning occurs after soldering, when all residual flux should be removed. This can be done with plain old isopropyl alcohol, or with a variety of special purpose flux cleaners. Leaving any residual flux is bad as the flux itself will cause corrosion. This is true even if you are using rosin core solder.

@Emoto -- start watching this old but quite excellent series on soldering. Don't let its age bother you, with the exception of some minor changes in soldering materials (like "RoHS") nothing has changed about soldering for a long time.

eta: get some scrap electronics. Hell, even an old clock-radio will do. Unsolder things. Solder them back together. In an hour you'll be an expert and confident. You'll need some flux, some solder, some solder wick (for unsoldering), and a good soldering iron with a selection of tips and adjustable temperature.

I love that series! Watched 9 episodes of it yesterday. I love the old school presentation style, and it covered a whole lot of stuff that I didn't know, which was great.  I need to watch more stuff on electronics soldering.

Yeah, I'm getting all new soldering equipment that should put out more heat and work better than the gear I still have from my childhood. As a child of 8 or 10 I developed an interest in soldering and found reasons to solder/unsolder various things, more because "melting metal is cool" than due to any real need. Played around with it through my teen years.

Later in life, I've used my meager soldering skills for automotive and motorcycle purposes (wiring).

I will definitely play around with the new gear and get a feel for how fast it makes the solder flow, etc., before attempting anything Mercury related.

I've never worn a ground strap. What do I clip it to and if I am wearing it and it is clipped to "x" do I need to avoid or do certain behaviors or anything?

This is turning into a soldering thread



Good on ya' for worrying about ESD! So many hobbyists neglect this, but it is so very easy to add into your repertoire.

Short answer: buy a wrist strap/ESD workmat kit (example). The strap lead will snap to the mat, and the mat should be grounded to an AC outlet. You can make that connection by cutting off a three prong AC plug and attaching the lead to the ground wire (not the neutral or, heaven forbid, the hot wire ). Your soldering iron should also be properly grounded. Wearing an ESD smock is even more cheap insurance, they are like $40 on Amazon, as are having some ESD bags and totes around. If you save just one IC all this shit will have paid for itself by avoiding the pain and agony of figuring out what is wrong, waiting for the new parts, and doing the necessary rework.

Finally, try to work in an area that is not carpeted, and if you can obtain an ESD safe workbench and chair even better. I have all that stuff that I was able to get essentially for free after 40 years in the electronics business. No ESD mat because the bench is ESD safe, but I do have a mat for when I want a soft work surface.

Attached File


ESD war story (long, don't read ): my last position was at a very small company. I was employee #11. They were a famous military training concern and one of their training classes was in basic electronics for let's just say a "very unique MOS". It was a good curriculum, real hands-on, with breadboards, soldering, all kinds of stuff. The guy who was teaching the course left with no warning my second week with the company. I wasn't hired to do that stuff, I was hired as a very senior gray-beard kind of dude. So they came to me and said "We need you down here at the training facility to teach tomorrow!" The training classroom was beautiful, with thick carpet, fancy stools and fancy workbenches. But a more wretched hive of ESD scum and villainy you would not find anywhere! No grounding. Nothing ESD safe. Lots of UnderArmour poly blend static generators We'd spend inordinate amounts of time handing out new ICs because the students would kill them repeatedly and their projects would stop working. After that first class I had a chat with the head of training. The next class they had smocks, mats, straps, totes and grounded soldering irons. Even with the plush stools and carpets they didn't lose a single chip and class was much smoother.

Another good video:

If the OP wants me to branch off into a new thread about building kit techniques, please say the word. I thought this thread was kind of about that. (?) @Flatlandbusa

I have a table that I intend to bring into my shack that will be dedicated to the build. It is just a regular 3' x 6' formica topped table with folding metal legs, and unfortunately, the room is carpeted. Am I doomed?

I'll get a good anti-static mat like was linked, and will ground my iron. Do I need to put those anti static things on my shoes, and/or what if I put down one of those plastic chair mats that are supposed to protect rugs? This kind of thing:


In browsing the kit instructions, this section on pg 9 (I made bold) gives me pause:

Step 6: Install the Antenna Module Board to the chassis:
A- Mount the Antenna board to the chassis using the remaining 4-40 Nuts (8)
Note: We always send an extra 4-40 screw and nut.
B- Solder the center contacts of the SO239’s and the RCA jacks to the board.
Note: You will have to carefully bend over the RCA jack center contacts to facilitate this solderjoint.
C- After soldering the SO-239 connectors in place, check with a multimeter for isolation.
between center pin and ground

How does one bend these things and what does the bending accomplish?

You are not doomed.

The shoe straps are for folks who wander around a production floor and can't be tied to a wrist strap. They only work with floors made with ESD safe tile. You don't need them. Just use your mat and wrist strap religiously. Not sure about the chair mat. They do make ESD chair mats but they are expensive and ugly. I think you'll be OK. You'll actually be many times better off than most hobbyists.

Cool. Thanks!