Comparing battery-powered phono pre-amps, from RS ($$) to ASR ($$$$) ... and beyond!

[D-500 Flogger]

There seems to be a lot of activity in the forum with people building/restoring/optimizing their vintage turntables. It's impressive just how far some have gone in order to bring these electro-mechanical marvels back to Day 1 (or better) operation.

Myself, prior to joining this forum my plan was simply to restore my old audio system & then feed it with a modded CD player supplemented by the occasional DVD and the obscure stuff only found on the internet. In other words, I didn't have plans to play any vinyl...

Of course, hanging out in here & seeing how much fun the vinyl & reel-to-reel crowd are having, it seemed only right to go ahead of see if I could tackle my old Dual 606 and undo the years of neglect. And if I'm going to do that, then I might as well see if I can bring back my first-ever preamp, a PL 2000.

****

Once I cleaned up the turntable & it seems to be ready for duty, now I was wondering how was I going to best take full sonic advantage of this analog input? Restoring the old PL 2000 phono stage was a given, but then again how would I be able to figure out (quantify) just how far away I was from today's State Of The Art? (As in, how do I ensure that I have the lowest possible background noise level when enjoying vinyl?)

****

One thing I've learned over my career is that the single hardest scenario to troubleshoot/fix/characterize/optimize/POOGE/hot rod/comprehend is when you only have ONE item to work with -- that is, no constant (unmodified) device to compare my progress against in order to keep from lying to myself...and others. (!)

Sure, with high quality test gear you can document the improvements made over time...the problem is, some of what makes us enjoy the listening experience the most seems to be just beyond the reach of what 'mere mortal' test equipment can resolve. (!)

****

So, when Gepetto pointed out that I could explore the area of battery-powered phono preamps featuring an affordable price of admission (plus the fact that this same preamp had created quite a stir in the audiophile community back in the day), I was instantly sold:



As a matter of fact, it was so affordable that I was recently able to further improve my test setup with a 2nd identical (think control) phono preamp -- it arrived early...today! From everything I can tell, it is actually a NOS cream puff:




To me, this is the best of all worlds, for I now have the opportunity to compare & contrast 3 different phono stages - eventually having the PL 2000 vs. a control unit vs. a unit upgraded by swapping out the old parts with today's low-noise/improved versions of the same. (!)

Done in a disciplined fashion, I can take this just as far as my interest in reproducing high-quality music from vinyl or my system's ability to resolve these differences will allow me to discern...

NOTE: To make sure that I'm not just deluding myself with 'expectation bias' my plan is to record the sound of the circuit in question, make the mod, and then record the same test tone or music sample again...and then by using this software be able to clearly define the difference made. (if any!)

****

The Perspective:

When you read my subsequent posts, please keep the following hand-drawn graph in mind.



Once I get the rest of the system restored, my plan is to then take these $20 battery-powered phono stages & see how far I can push them from their 'near zero' starting point towards the knee of the curve on this hand-drawn graph.

Of course, in the unpopulated state the curve above is a pure abstraction that conveys no meaning, so I am going to populate it with a selection of battery-powered phono stages for sale *right now*. Admittedly this is an unscientific sample...but at the same time, my hope is that it provides some food for thought for anyone else tinkering with their vinyl in 2022.

FWIW --

 

[NeverSatisfied]

There seems to be a lot of activity in the forum with people building/restoring/optimizing their vintage turntables. It's impressive just how far some have gone in order to bring these electro-mechanical marvels back to Day 1 (or better) operation.

Myself, prior to joining this forum my plan was simply to restore my old audio system & then feed it with a modded CD player supplemented by the occasional DVD and the obscure stuff only found on the internet. In other words, I didn't have plans to play any vinyl...

Of course, hanging out in here & seeing how much fun the vinyl & reel-to-reel crowd are having, it seemed only right to go ahead of see if I could tackle my old Dual 606 and undo the years of neglect. And if I'm going to do that, then I might as well see if I can bring back my first-ever preamp, a PL 2000.

****

Once I cleaned up the turntable & it seems to be ready for duty, now I was wondering how was I going to best take full sonic advantage of this analog input? Restoring the old PL 2000 input stage was a given, but then again how would I be able to figure out (quantify) just how far away I was from today's State Of The Art? (As in, how do I ensure that I have the lowest possible background noise level when enjoying vinyl?)

****

One thing I've learned over my career is that the single hardest scenario to troubleshoot/fix/characterize/optimize/POOGE/hot rod/comprehend is when you only have ONE item to work with -- that is, no constant unmodified device to compare my progress against in order to keep from lying to yourself. Sure, with high quality test gear you can document the improvements made over time...the problem is, some of what makes us enjoy the listening experience the most seems to be just beyond the reach of what 'mere mortal' test equipment can resolve. (!)

****

So, when Gepetto pointed out that I could explore the area of battery-powered phono preamps featuring an affordable price of admission (plus the fact that this same preamp had created quite a stir in the audiophile community back in the day), I was instantly sold:

View attachment 60209

As a matter of fact, it was so affordable that I was recently able to further improve my test setup with a 2nd identical (think control) phono preamp -- it arrived early...today! From everything I can tell, it is actually a NOS cream puff:

View attachment 60210


To me, this is the best of all worlds, for I now have the opportunity to compare & contrast 3 different phono stages - eventually having the PL 2000 vs. a control unit vs. a unit upgraded by swapping out the old parts with today's low-noise/improved versions of the same. (!)

Done in a disciplined fashion, I can take this just as far as my interest in reproducing high-quality music from vinyl or my system's ability to resolve these differences...

NOTE: To make sure that I'm not just deluding myself with 'expectation bias' my plan is to record the sound of the circuit in question, make the mod, and then record the same test tone or music sample again...and then by using this software be able to clearly define the difference made. (if any!)

****

The Perspective:

When you read my subsequent posts, please keep the following hand-drawn graph in mind.

View attachment 60211

Once I get the rest of the system restored, my plan is to then take these $20 battery-powered phono stages & see how far I can push them from their 'near zero' starting point towards the knee of the curve on this hand-drawn graph.

Of course, in the unpopulated state the curve above is a pure abstraction that conveys no meaning, so I am going to populate it with a selection of battery-powered phono stages for sale *right now*. Admittedly this is an unscientific sample...but at the same time, my hope is that it provides some food for thought for anyone else tinkering with their vinyl in 2022.

FWIW --

Will be watching with interest.
For most of my audio life, I completely avoided records, fully believing that it was a fool’s errand because digital was superior in every way. Other than my first turntable back when I was a teenager I hadn’t owned one in close to 35 years, until about 2 years ago.
That’s when I got my first PL8000 just because I wanted a complete PL system from turntable to speakers and not because I thought i would use it much. Man was I wrong about vinyl, I FINALLY get it. It not only sounds more alive but the act of getting up out of the chair to change records keeps me more focused on the music. Meaning that often after loading 5 CD’s in the changer or firing up the streamer, it wouldn’t be very long before I was dosing off or not really paying attention to the music.

 

[J!m]

Phono preamps. Yeah.

We have a short list of goals, which conveniently inter relate and conspire against one another.

High gain
Low noise
Accurate RIAA time constant

In general, the answer is: “pick any two”.

Wyn Palmer (Ph.D., but he doesn’t bother with it) used to design IC chips. Op amps we all know and love, among other things. Generally frowned upon by the hi fi community- everything must be “discrete and rare and expensive” or it’s crap. They have a similar opinion of switching power supplies.

So, (just as a kick to the nuts of the industry I suspect) Wyn decided to design a phono preamp with op amps and a switching power supply.

Well, it kicks ass. Noise is very low. RIAA accuracy it within mdBs; not dBs. Plenty of gain available for the lowest output moving coils (no transformers and their distortion), bandwidth is massive.

It uses a cheap MeanWell switching power supply, and a filter board he designed to attenuate every bit of hash that comes out of it.

I built one. It’s scary good. He’s built several for audiophile friends, who went on to sell off their “esoteric” preamps. It easily holds its own in the “over ten grand” phono preamp club

But I like the idea of battery power. I think there was discussion of one Wyn did that ran off a pair of 9V batteries- maybe four of them, because it’s a +15/-15 power supply.

One “trick”Wyn did, that I think it critical, and a deviation from every other preamp (as far as I know), is he divided the RIAA time constant correction into two stages. He has two gain stages and one set of corrections is within the first stage and the others are in the second. I think that was key. Predominately TI chips throughout. They have great specs I’ve seen first hand shopping for replacements for my DAC. plenty of local power conditioning- right at the chips, which are each within a fortress of film caps.

I’ll try to post the specs tomorrow. But listening is something else! Mine is still messed up with the balance pot wiring, but even putting it in mono, it’s just crazy good. Bad in a way because you hear every spec of dust but on a good record it’s scary good.

He also did a headphone amp, using the same power supply and I love it. Wide bandwidth massive headroom and simple. Three chips and the rest is discrete. It doesn’t even use the filter board for the power supply (can’t really, because it ends up limiting current)

The man is a brilliant EE but also an audiophile. No BS just quality designs.

 

[D-500 Flogger]

OK, our first step up, money-wise, is a used MC (moving coil) head amp** that has a lot of street cred & has held it's value over the years -- the SOTA, designed by John Curl. On eBay it's on offer for $869:



Here's the end (connector) view:



Battery side of the module:



The other side, showing the components:



NOTE: Instead of linking directly to eBay (and having the photos disappear down the road after the auction ends) I've decided to use screen grabs.

For what it's worth, I highly recommend that the reader poke around the interwebs & read up on John Curl's design. It's a fascinating read...and just by looking at the photos I can see that Mr. Curl believed in further lowering the impedance of the batteries with plenty of local capacitor storage.

** In an interview, John Curl was careful to point out that since this outboard 'head amp' was just to lift the MC cartridge output up to the level needed by the MM (phono) input, there is no RIAA circuitry aboard. (!)

 

[D-500 Flogger]

Will be watching with interest.
For most of my audio life, I completely avoided records, fully believing that it was a fool’s errand because digital was superior in every way. Other than my first turntable back when I was a teenager I hadn’t owned one in close to 35 years, until about 2 years ago.
That’s when I got my first PL8000 just because I wanted a complete PL system from turntable to speakers and not because I thought i would use it much. Man was I wrong about vinyl, I FINALLY get it. It not only sounds more alive but the act of getting up out of the chair to change records keeps me more focused on the music. Meaning that often after loading 5 CD’s in the changer or firing up the streamer, it wouldn’t be very long before I was dosing off or not really paying attention to the music.

It *is* a whole different experience. I distinctly remember buying a new album, loading it ever so carefully onto the TT, headphones on, and then listening to the new album while studying the cover art / liner notes / back of the album cover intently. I can *still* remember buying my own copy of Robin Trower's "Bridge of Sighs", dropping the needle, and being transported to another place...

Now to see if I can combine both the nostalgia with the kind of real-world performance that J!m is describing in his reply -- it will be well worth getting a serious focus on... :0)

 

[D-500 Flogger]

Phono preamps. Yeah.

We have a short list of goals, which conveniently inter relate and conspire against one another.

High gain
Low noise
Accurate RIAA time constant

In general, the answer is: “pick any two”.

Wyn Palmer (Ph.D., but he doesn’t bother with it) used to design IC chips. Op amps we all know and love, among other things. Generally frowned upon by the hi fi community- everything must be “discrete and rare and expensive” or it’s crap. They have a similar opinion of switching power supplies.

So, (just as a kick to the nuts of the industry I suspect) Wyn decided to design a phono preamp with op amps and a switching power supply.

Well, it kicks ass. Noise is very low. RIAA accuracy it within mdBs; not dBs. Plenty of gain available for the lowest output moving coils (no transformers and their distortion), bandwidth is massive.

It uses a cheap MeanWell switching power supply, and a filter board he designed to attenuate every bit of hash that comes out of it.

I built one. It’s scary good. He’s built several for audiophile friends, who went on to sell off their “esoteric” preamps. It easily holds its own in the “over ten grand” phono preamp club

But I like the idea of battery power. I think there was discussion of one Wyn did that ran off a pair of 9V batteries- maybe four of them, because it’s a +15/-15 power supply.

One “trick”Wyn did, that I think it critical, and a deviation from every other preamp (as far as I know), is he divided the RIAA time constant correction into two stages. He has two gain stages and one set of corrections is within the first stage and the others are in the second. I think that was key. Predominately TI chips throughout. They have great specs I’ve seen first hand shopping for replacements for my DAC. plenty of local power conditioning- right at the chips, which are each within a fortress of film caps.

I’ll try to post the specs tomorrow. But listening is something else! Mine is still messed up with the balance pot wiring, but even putting it in mono, it’s just crazy good. Bad in a way because you hear every spec of dust but on a good record it’s scary good.

He also did a headphone amp, using the same power supply and I love it. Wide bandwidth massive headroom and simple. Three chips and the rest is discrete. It doesn’t even use the filter board for the power supply (can’t really, because it ends up limiting current)

The man is a brilliant EE but also an audiophile. No BS just quality designs.

J!m, we're definitely on the same page here. I think that you are going to like how the price/performance curve is going to populate itself. And yes, from everything I can gather the noise-eliminating benefits of battery power is (of course) ever more beneficial the lower the level of the music signals we are trying to shepherd through our equipment. So obviously the phono stage is the best place to discern a difference between a circuit propped up with AC>DC power supplies vs. the same circuit on pure battery power...

 

[J!m]

I think a line preamp can benefit from pure DC as well.

I envision an outboard power supply (pretty typical) but with a bank of batteries inside. When you turn the power “on”, you are actually disconnecting the charging batteries from the AC line, and connecting that juicy DC to all the goodies in the other box, hungry for electrons.

I guess I’m not the first nut job with this idea, but it just makes sense. At least as much sense as a gross of capacitors to smooth the AC into low ripple DC. I think the cost : performance ratio would favor this contraption.

 

[D-500 Flogger]

I think a line preamp can benefit from pure DC as well.

I envision an outboard power supply (pretty typical) but with a bank of batteries inside. When you turn the power “on”, you are actually disconnecting the charging batteries from the AC line, and connecting that juicy DC to all the goodies in the other box, hungry for electrons.

I guess I’m not the first nut job with this idea, but it just makes sense. At least as much sense as a gross of capacitors to smooth the AC into low ripple DC. I think the cost : performance ratio would favor this contraption.

BINGO!

Although the shared goal is to somehow figure out a way to create the illusion that the 'musician is there' in the room with us...the sport is figuring out how to accomplish this without having to spend cubic dollars to do it...that (unfortunately) I didn't bring to the table. (ie: My audio ears have always been bigger than my wallet can stomach... :0)

 

[J!m]

Caviar taste on a cracker budget won’t cut it.

You’ve gotta at least pony up for a burger.

my expectations may be a bit high because for about 45 years I’ve been playing with musicians. (The first few sucked like a black hole) but eventually my skill, and the skill of those around me grew to the point where very few people covered their ears.

Point is: I have a good idea of what instruments sound like. Not just 80’s hum bucket guitars through a rack of processing gear; also strings, horns, reeds and of course percussion of every sort.

To me, if I think it sounds real, it sounds real.

I got a taste of that already, and I think (hope) my updated table and new phono preamp will keep me comfortably in the “HOLY SHIT!!!” zone.

 

[D-500 Flogger]

The next step up from the (early '80s vintage yet still respected) John Curl SOTA is the 2005 Sutherland PhD. A previously-enjoyed unit is currently on eBay, offered for sale for $1869. (free shipping)



A peek under the hood reveals no less than 16 alkaline 'D' cells provide the power to this MC head amp:



FWIW, I also found a Stereophile review written by the Michael Fremer, supplemented with plenty of graphs for the gear heads in the audience.

Still battery powered...but a long ways away from the humble RS amp that's packaged in a case the size of a pack of cigarettes...

 

[J!m]

$1800 and ya couldn’t do better than the cheapest Amazon batteries?!? WTF?

I wonder if those yellow things are op amp modules, similar to Levinson and old recording consoles (where Mark no doubt got the idea).

I chatted with Wyn about these (formerly discrete) op amp modules, thinking some of his parallel chip op amp trickery could drive noise and distortion way down and he seemed insulted. Discrete was the best they could do at the time. A chip has the advantage of an enclosed thermal envelope so performance is very predictable with change in temperature during use.

Know anyone with an old analogue synth? Like a Moog or Oberheim? Tuning them is an absolute nightmare. You have to throw a blanket on it and get it hot before you even start. Massive tuning drift with temperature. Perfect example of discrete component behavior- parts heat at different rates and their values change.

If you can hear it there, do you think you can hear it in other things?

 

[D-500 Flogger]

So I've found in the past that when I start out on an upgrade project, it helps to do a big-picture "min-max" review. In other words, before I attempt to improve something modest like the RS phono preamp, I should first acquaint myself with every offering in this space, from the most affordable...to the product held up as the bleeding edge of attainable performance. This way I better understand how & why the performance tradeoffs were made along the way.

From what I can tell, in the land of battery-powered phono stages, the ASR Basis Exclusive is right up there at/near the pinnacle. On eBay there is a used one in very good condition on offer right now for a cool $7839. (free shipping, though :0)



Here's a bird's eye view of the board populated with the components:



According to the designer, he didn't like the sound of the circuit inside a metal enclosure...so here's a photo of the thick (acrylic?) walls that makes up the enclosure:



Here's a shot of the rear panel, showing the RCA connections, the Balanced connections, and the large shielded DC power cord that goes down to the (40-50lb) battery box. (Seems as if the music signal from the TT to the preamp is a pretty heavy lift, requiring extraordinary battery & capacitor measures?)



And here's a photo showing a small corner of the battery box w/logo:



Good news! Instead of me having to buy this in order to share an opinion, Stereophile's Michael Fremer has already reviewed this unit, and there are plenty of graphs to ponder. (J!m, this article will require a big bucket o' popcorn -- be sure to make that first before diving in! :0)

NOTE: As I'm sure that anyone reading this already knows, the steep vertical ascent on the right hand side of the price/performance curve illustrates the Law of Diminishing Returns. And although I can appreciate the sheer effort that this *phono preamp* entails, if I buy this in NY the sales tax *alone* is an additional $627!

So, although it might be a bit rich for me...it could be just the ticket for thee!

 

[J!m]

So, it sounds better to have delicate signals from a moving coil going into an unshielded plastic box?

Im an idiot but I’ve gotta call bullshit on that.

I think we’re all foolish to not embrace a balanced line from the table to the phono preamp. Take advantage of the noise rejection of a balanced line! It just makes sense! It’s lower than a microphone output, and those are balanced.

 

[D-500 Flogger]

$1800 and ya couldn’t do better than the cheapest Amazon batteries?!? WTF?

I wonder if those yellow things are op amp modules, similar to Levinson and old recording consoles (where Mark no doubt got the idea).

Here's an extreme blowup on one of these modules. Check out the 45 / 50 / 55/ 60 db markings in the corners:



The following is quoted from the Stereophile article:

"Instead of computer-grade DIP switches, the PhD has four unique plug-in circuit boards: two for gain, two for loading. How they're oriented when they are plugged into the mother board determines the setting. The loading choices are 100, 200, 1k and 47k ohms; the choices of gain are 45dB, 50dB, 55dB, and 60dB. Or you can get blank boards and roll your own."

So, instead of fiddling with dip switches, you simply rotate these modules until you get the desired result...

 

[D-500 Flogger]

$1800 and ya couldn’t do better than the cheapest Amazon batteries?!? WTF?

I wonder if those yellow things are op amp modules, similar to Levinson and old recording consoles (where Mark no doubt got the idea).

I chatted with Wyn about these (formerly discrete) op amp modules, thinking some of his parallel chip op amp trickery could drive noise and distortion way down and he seemed insulted. Discrete was the best they could do at the time. A chip has the advantage of an enclosed thermal envelope so performance is very predictable with change in temperature during use.

Know anyone with an old analogue synth? Like a Moog or Oberheim? Tuning them is an absolute nightmare. You have to throw a blanket on it and get it hot before you even start. Massive tuning drift with temperature. Perfect example of discrete component behavior- parts heat at different rates and their values change.

If you can hear it there, do you think you can hear it in other things?

J!m, I understand your legitimate thermal concerns -- and the bigger the device, and more scattered your discrete components, the more that getting all the individual components, each to their ideal thermal operating point (so that they can give their best contribution to the circuit they are in) is like herding cats.

Given the above, maybe we should skip the $1800 PhD and go for the $7839 Basis, for it is designed around some Analog Devices op amps. Quoting from the Stereophile review:

"The heart of the Basis Exclusive is a super-quiet Analog Devices microphone preamp based, believe it or not, on op-amps. According to the manual, after the adjustable linear gain stage, the signal passes through a passive low-pass RIAA filter and the low-frequency cutoff switch, followed by active RIAA equalization. The low-impedance unbalanced signal can then be output directly. An additional driver circuit is used for the balanced output signal. Only polypropylene and polystyrene capacitors are used in the signal path."

****

Again, the goal of this exercise is purely food for thought. Right now, I'm not advocating, just trying to get the lay of the land. One thing I can say, however, is that I haven't seen anything so far that would talk me out of experimenting with battery powered line-level circuits -- if anything, the reviews talking about the music emanating from a black background are persuasive...

 

[D-500 Flogger]

So, it sounds better to have delicate signals from a moving coil going into an unshielded plastic box?

Im an idiot but I’ve gotta call bullshit on that.

I think we’re all foolish to not embrace a balanced line from the table to the phono preamp. Take advantage of the noise rejection of a balanced line! It just makes sense! It’s lower than a microphone output, and those are balanced.

Given my own preoccupation with the big increase in background RFI levels in today's homes, I agree with your comment on handling the low-level phono signals in an acrylic box. Of course this isn't the first time I've encountered an equipment designer that eschewed a conventional metal box because they didn't like the way their circuit sounded inside it. For example, at the very origin of the phono signal path this cartridge was designed with a specifically-chosen case because of the way it affected the sound:



At first glance it seems a bit crazy...but if wood is what it takes in order to achieve the 'vocal verisimilitude" ...then maybe I have no choice but to pony up for this Brazilian Rosewood beauty?

 

[D-500 Flogger]

Seriously, I actually *do* believe that a really highly resolving circuit could be (de)tuned by the interaction of a metal enclosure tightly surrounding it...but my understanding of electronic theory says that the inverse-squared law is involved, so if you take the same circuit and place it in a bigger metal enclosure then you get the best of both worlds -- isolation from external RFI fields + the sound of the circuit sans the stray inductance/capacitance of a too-close case?

What does any of this have to do with the RS boxes on my desk? Well, once I get all that I can out of the hot-rodded RS module, since it *is* in a small pack-of-cigarettes sized case, I'll have to be sure to compare the performance of the circuit inside vs outside it's metal container while playing a Nora Jones selection. (!)

 

[D-500 Flogger]

So, does the top-shelf battery powered phono preamp provide the ultimate vinyl listening experience?

Well, according to Michael Fremer, the $7800 ASR Basis Exclusive is really close to the ultimate listening experience...but, if you really deserve the very best, then you will have to go get yourself a Boulder 2008 Phono Preamp. The price of admission? $29,000.

Straight from the horse's mouth: Boulder 2008 Phono Preamp Stereophile review. (NOTE: You guys with the Audio Precision System 1 test equipment should at least look at the measurements on the last page of this article.) Essentially the test dude had to inject huge signals (on the order to 200mV to a normal 5mV MM input, or +32db!) in order to get *anything* to come up out of the noise floor -- this equipment is ready for the hardest pounding that Vika can put to the piano! :0) Seriously, the sweeps are pretty pristine.

****

I almost forgot, the $29K is only for the phono preamp. The matching line level preamp is an additional $36,000. ($65K total -- J!m, that will buy a lot of burgers, wouldn't you agree? :0)

 

[derek92994]

Interesting info there, funny how this thread appeared today. George (Pennysdad) recommended an $18 phono preamp which runs off a 9 volt battery (Thank you George!) I purchased one which arrived a couple of days ago. I didnt think it would be any good, but after hooking it up, wow, for $18 this thing sounds fine. Clean and balanced. Really exceeded my expectations. My usual phono pre is a $500 Project Tubebox DS which Performs very well. Big difference in price there. But for now, I am enjoying the battery powered one, its always good to try new things and they are handy to have as a spare.

 

[D-500 Flogger]

I think a line preamp can benefit from pure DC as well.

I envision an outboard power supply (pretty typical) but with a bank of batteries inside. When you turn the power “on”, you are actually disconnecting the charging batteries from the AC line, and connecting that juicy DC to all the goodies in the other box, hungry for electrons.

I guess I’m not the first nut job with this idea, but it just makes sense. At least as much sense as a gross of capacitors to smooth the AC into low ripple DC. I think the cost : performance ratio would favor this contraption.

J!m, you aren't the first nut job -- actually, you are in good company, for Paul McGowan (of PS Audio & Genesis {Arnie Nudell} fame) tells the story of how his successful career started with a battery-powered phono amp in a Roi-Tan cigar box destined to fix a FCC-flagged hissy FM radio station. It's a great story...and I even enjoyed the comments afterwards. (1 of which includes a reference to John Curl's SOTA.)

Fun stuff!