Expired beverage

Sad thing is that because of a bunch of crazy stuff in my personal life I've not had time to operate much or blog at all.  Around early December, I finally got a Beverage antenna up (with respects to the late Dr. H. H. Beverage).  I just took out the portion of it that crossed the rented land for the farmer.  I used it three times.  Apparently I have a strong noise source in my house somewhere that I have to debug (uugh), but I was able to phase it out with my modded MFJ-1025.  I had a bit over 1000' feet up in December...

Above is the portion of the plowed field.  I took that out last Sunday  :O(  But I still have about 700' left in the woods and it appears I can expand it out in another 200-250' year around.  :O)

My house and garage are oriented NE of the antenna, of course, so the two wire is needed.  With the local noise source that worked out well anyway.

Above is the section in the woods.  I can go farther.  If I can get my neighbor to agree to let me go into his land a little I can get back the 300' or so feet I lost in the field.  If not, I can go 800-900' permanently.

In  the Midwest, our ground is a little better than is posted in most of the handbooks.  It appears on better soil, longer Beverages work better than on either coasts.  My 1000' long one was FAR INFERIOR to my friend Jeff Woods, W0ODS 1/2+ mi long antennas on almost all bands.  I could hear Algeria on Long Wave with this antenna-- it was full quieting on his.  He's heard Commando Solo in Afghanistan at 3 MHz before on one of his Beverages.  It's cool stuff if you live in the country.

He taught me the appropriate method of constructing these to survive the rather windy Iowa winters..  That is 16 ga Aluminum electric fence wire.  Proper fence posts (cast, not "bent") and 1-1/2 PVC, no smaller.  Holes to run the wires through with slits cut in with a hacksaw (or in my lazy case a diamond saw from Harbor Freight with the holes Dremelled out).  Here is a picture:

This works out really well.  The transformers were homebrew.  I use "Balun" type cores, mix 73 because I had them... two cores wrapped together.  The MFJ antenna analyzer is very useful for proving them out before hooking them up.  I ought to post something about that but that'll take time I don't have now.

Anyway.. the sad thing is I used this 3 times during my Christmas break and that's it.  I miss ham radio and writing about it.  Maybe I'll get back to it again.

I can run a shorter one year around.  But the bad thing is that I need like 300' of RG-6 (times two) to get to the wood part of the Beverage.  Ideally, a remote controlled phase box with the Beverage pre-amped would be the ideal setup.  I don't think anyone makes one.  Yet..  Another project I can start and never finish... sigh.  But it would be cool to have a phase box at the beverage termination (at the right impedance w/o a transformer at the fed end even) and then amplify out the 300' of cable.. it's a receive antenna anyway so it's very possible.

In the mean time I'm going to post a few words about a relatively new hobby I can do at least 1x a day.. that's coffee.  I'm going to start a new blog, "Cheapskate Coffee" and write a little about the beginnings of Specialty coffee and home roasting but without spending a fortune.  I will eventually spend a fortune on that too I suppose.. but not yet.

Until next time.. hopefully not 6 months... 73

Arrgh....*poof*..

The DigiLite DATV project has taken me on an interesting (and kinda expensive) tangent in the last few days.

About 2-3 years ago, after years of doing small Micros and PIC processors, I decided to try out the AVR and the open source WinAVR GCC tool chain for the AVR's.  I never did get into Arduinos except for hardware-- I bought a few Sanguino boards which are an ATMEGA 644P version.  I got shipped 644's instead of 644P's and it wasn't worth shipping back (my order was correct, the shipment wasn't).. so I used those.

I decided that for the DigiLite DATV project to make my own programming board for the "Ultram Tech" PLL board rather than using the BATC Closed source or F1ACN "demo PIC basic" solution.  Initially, I didn't want to do the software work required to use WinAVR (see previous posts when I was working on the HF amplifier-- which I will get back to someday!), so I decided to see how "beneath me" the Arduino IDE actually is/was.

I'm actually fairly impressed by it because it does actually hide the GCC tool chain within it so the actual hit to the performance and RAM is minimal.  It is really well designed.  In the meantime I decided to order off a Chinese clone of a Arduino 2009 and  a LCD shield to go with it.  It cost $29 shipped for both.  It will be the "GUI" for the PLL project.   The physical packaging is nice.. it'll be nice and really that inexpensive PLL with the inexpensive control could also make a really nice "poor man's microwave signal generator".  The commercial Arduino 2009 version has a FTDI serial chip on it so ideally my version will have both a 2x16 LCD display and also USB (CDC serial emulation) control over the PLL.  I'm getting more functionality out of this unit for less work and $ than the two PIC based solutions.

I think I am going to post on Amateur Radio.com a "Zen of Arduino for Ham Radio" describing the potential uses of these little devices and a small quick tutorial (maybe here if it gets lengthy or too technical).  Anyway.. all is well with that project.. It took me about 20 minutes to build up a Sanguino and a HD44780 display and write 80% of the GUI for the PLL.  This was before I got the e-bay modules (which are quite nice).  To port off to the real Arduino (ok clone) took literally 10 seconds.

I'd have the whole thing done now.. but I need to figure out the control words for the PLL chip... this will be easier when I actually receive the PLL.

I can see the reasoning for "Arduino" even though those are slow, 8-bit processors that are a bit pricey for what they   are... but for someone who wants not to delve into programming these are ideal.

Anyway.. I also decided that I should use these to teach the older boys how to start programming rather than starting them off on Linux or MS Visual Studio.  So I got the "wild hare" up to dig out another old project--

About three years ago I bought a WizNet812MJ (W5100) module for about $35 with shipping (which was expensive IMHO) to do the DVB-S project on a FPGA.  The intent was to use Ethernet at the max 20 Mbps SPI rate the W5100 was more or less capable of.  I did get it to go with a small micro, but at the time the code to do the stack was substantial and I ran out of time.  In the closet that module went.

I decided, hey, the Arduino Ethernet Shield is basically the W5100..the arduino has a nice library for it.. no work, right?   So I made a breakout for the breakout, and put a L78L33ACZ 3.3V regulator on it and wired it into a breadboard.  What I didn't realize is that on the Sanguino board the SPI is currently "broken" on Arduino >-019 .. it's fixable but it's not a simple fix.

I almost had it.  (It has to do with the Arduino code not knowing the different pinouts of the SPI UART on the ATMega644)..

This is only a minor ARRGH.. though.. I was on my way to find out the issue with the module..  It is, by the way 3.3V but 5V tolerant for the inputs.  One thing that has to be done is resetting the chip.  I did this by tying into the RESET on the Sanguino.  I didn't yet (I'm getting some from...yes..e-bay china) have the little push button reset buttons.  So I have been resetting with a jumper wire.

Well.. guess what I did when I almost had the SPI issue resolved on the Sanguino/ATMega644/Wiznet?  I bumped the unregulated voltage when resetting it.  The Wiznet W5100 is 5V tolerant.. but it's not 8V tolerant!  :O(  The LCD was fine and the ATMega was fine.. no it couldn't have been something I had multiples of that is easy to get.

So it happens to all of us I suppose.  The bad thing here is that it costs about $25/module now with shipping (I did buy two more because I do have a couple of future projects and I want to teach the kids by making a little sensor driven Internet device-- weather station maybe?) and I also decided to buy an actual shield from.. yup... China.  I wondered why the lines on the Arduino shield are buffered on a 5V tolerant chip.  I now know.  So in a millisecond it cost me about $75.  OK the $25 for the shield was coming anyway probably.. but $50 for two more modules.. not so much.

Lesson:  don't do something that stupid.. or if you do put the chip reset on a GPIO line!

The good news (as it is) is I fired up the X-Tronic hot air gun and got the chip off without totally destroying the board.  (It looks good and I didn't drop off anything from the bottom!)  So if a place that charges reasonable shipping (Saelig is out, for example) and doesn't require minimum order of 5 of them (like WizNet direct or Jameco).. I can fix the module.  SparkFun carries them but are out of stock.  So if a SparkFun guy sees this I'd like the $6 solution to the $4 problem too to fix the module I have.  !

Like ham radio.. electronics is an expensive hobby.  But I do love it and I guess since it became my life and living I am blessed.

But boy do I feel downright dumb tonight.

DigiLite update...and SOAPBOX

I did go off and order about $150 total worth of parts for the DigiLite.. I'd guess to get to the "modulator stage" of a DATV DVB-S transmitter that one would need about $275-300 if buying all new.

I also ordered the $55 Ultram Tech (from Israel..e-bay) ADF4360-6 based PLL oscillator board.  I am going to write my own control that will use a $29 Arduino 2009 board and a 2x16 HD44780 based board with buttons from e-bay (China) rather than running the "5-button" PIC board hack-up the BATC is running.  I need to be able to set my own frequencies, so I need source!  I have most of the code done already (Arduino is sooo easy..) but I need to figure out some of the settings that the Analog Devices Integer-N PLL / OSC uses.. like "current setting" and "antibacklash".  I don't have the Arduino yet.. but I converted some of the Sanguino's that you'll see in earlier posts to actually be Arduino based instead of hacked with WinAVR as I had been using them.


And Yes.. If I do this, it would be a "bang up" poor mans signal generator for 1200-1400 MHz.  Code will be open source...   Note also that there is a French Ham doing a version and there appears there may also be  a board when the BATC CQ-TV 235 comes out in October 2011..  okay.. we are past that.. now.. so "soon."

I ordered $80 of parts from Mouser for the Chip Tantalums (expensive!** only one is really needed for the DSPic33) Bourns Surface mount trimmer pots.. weird SMT 3.3V regulator***, a couple of PICs, and adjustable regulators for the biasing of the IQ circut.. and other bits).. oh and the $27 FTDI module.  By **expensive-- I'd eliminate the stinking chip tants-- which I hate-- if the board was re-laid out and replace with common leaded electrolytics.. I'd use standard leaded pots, ***a leaded 3.3v 78L33 type regulator.. those little things would make the board an inch bigger in one dimension but probably cut the parts cost by $15.)  I'd also consider the four port FTDI module FT4432 instead of the FT2232 and use one of the extra ports for SPI programming of the Ultram Tech PLL Oscillator and .. maybe an extra RS-232 port with a line driver on the board?  Actually, why not put the PLL chip on the board as well and not have to buy the synth from Israel?  (No offense here to Ultram Tech.. good service so far)

All parts can be had from Mouser which is the cheapest overall source other than the Analog Devices modulator chip.. the AD8346ARUZ..  that is a Digi-Key or if you must Newark part.

I programmed my own DSPic and saved the BATC pre-programmed one for a second board.  I was going to also order another board from the UK and build it up for 70cm.  I can't do that.  I do NOT believe it is legal to do so in the US.  Many including N1ND who is the frequency rules guy at the ARRL disagree with me.  I'll briefly mention why I do not think that DVB-S/C/T or even ATSC is legal on the ATV frequencies on 70cm at the end of this post.   I might build a second 1255 MHz unit and loan to other local hams so we could do a two-way.. or maybe I'll eventually build up a 33cm unit.

Anyway.. interestingly enough.. the DIP adapter for the PICKit3 I bought to program DIP based PICs wouldn't work the DSPic33... but a breadboard did!  If there is interest I'll write up how to make the programming on the breadboard with the PICkit3.  Basically hook up the power to the right places and the ICSP lines and power from the PICKit3 and it works!  The lesson here:  the bread board is the UNIVERSAL dip adapter.. don't waste the money of the ZIF adapter board unless you are programming a lot of parts!

Anyway.. I don't want to ramble to much, so lets cut to the chase.  I don't have the Oscillator module yet, so
I fired the unit up with no LO drive and no MMIC pre-driver installed...

It works...  At least up to the modulator out from the DSPic33..  Here is a short video of a "government cheese" NTSC SD-box receiving PBS on the Hauppage PVR-150 with WinTV-6 and then streaming it out with the BATC's software to the PIC which at least thinks it's modulating the signal to QPSK (and would if I had a LO and properly adjusted the I/Q offset/drive).  So it's really close:

So yeah.. it works like greased snot.  It's slick.. and impressive.  There are a bag of tricks to make this happen like the MPEG-2 Conexant chip on the PVR-150 configured (in that case, for 3000 MSym/s and 1/2 FEC for 3 MHz wide signal) for a CBR MPEG-2 NTSC D1 video rate of 2222 and MP2 audio rate of 128K which is really quite sufficient for ham use.. actually.. I'd like to experiment with narrower signals!

At 2222/128 the null packets are very small and most times there is negligible PCR lag.. occasionally though the start-up seems to throw off the DSPic33 at this rate and a restart is necessary for a non negative PCR lag.  at 2112/128 this seems never to happen but null packets are about 4.5%.. so somewhere in the middle of the two is probably perfect if you want to run 3 MHz wide D1 Video with decent, but not-quite music quality stereo audio!  That's at least 1/2 the bandwidth of analog ATV.

<SOAPBOX>

Meaning this should be a shoe-in for the 70cm band!  Much better than 2x the quality and 1/2 the bandwidth! Super lets start using it?  Not in my opinion.  Part 97 defines image on Frequency and/or Phase Modulated signals as designator F2F or G2F only.  Commercial definition from researching license grants to commercial parties show that ATSC is 5M38C7W (or in ham speak C7W) and DVB-S as G7W.  No exceptions.. I did not find ATSC defined as C2F or DVB-S defined as G2F anywhere!   These designators are explicitally defined in Part 97 as "multiplexed data". "7" and "W" are excluded from Image!  So even though there is a clause that states that undefined or digital modes that are substantially the same as the analog equivalent in bandwidth for phone and image are legal.. Legally DVB-S/C/T and ATSC isn't IMAGE.. it's DATA.  And data is (WRONGLY!) limited in the 1980's rules as 56K baud (symbols per second per carrier) and 100KHz BW .. so even though NTSC video is not legal anymore anywhere else.. ATSC is mandated.. it's illegal in 70cm under current rules but NTSC isn't.

Yeah, would the FCC enforce this or care?  Nope.  The ARRL doesn't care either apparently.  It doesn't change the fact this is what the law says.  This is a warning, people.  The rest of the world is going digital and as hams we are not.  Are rules are a major reason why.  They were intentionally set up in the 1980's to make digital modes second class citizens on the ham bands.. or at least new digital modes.

If you disagree with me and run DVB-S/S2 or DVB-C and some have on 70cm... good luck and I wish you well-- I support you.. but I see it as not permissible.. which is really quite unfortunate.  It's legal in most other countries that don't have protectionist rules in their regulations.

End of my comments on this... </SOAPBOX>

One time rant, get it off of my chest.. then the DigiLite from BATC

Well, now that you can tell that I only am posting short messages once every three months or so, that life has gotten in the way of my other plans... including ham radio.

I've not been on the air since June or so, and had severe house and antenna damage in early July that-- although the monetary loss was minimal, took a lot of my SUMMER free time to fix.  I would often operate from the W0CXX club station at work, but they are re-roofing the building, and there are no usable antennas there either for quite some time.  So ham radio has been on hold.

I'm probably back to operational on 40m (at least with a low dipole), pretty sure I'm operational on 20-15-10m. My previously poor 75/80m tower feed can be fixed.. but with the 'spots being what they are lately I'm not in a hurry with that.

I want to complete my 12m/17m Moxon/Yagi combo that I've been building out of an old 10m Cushcraft beam. (When I prove that it works I'll post a 'blog entry on it here with an overview at Amateur Radio.com.)   I have a 6m 5 element beam ready to put on a roof tower on the opposite side of the detached garage from where I have the tower.  It will be a little lower in elevation but should be fine.  This has been in the works since spring.  I was also going to put up two verticals phased on 40m (and eventually load it for 80m) but I don't see that happening in 2011.  Sigh.. for a while there I was really productive with the hobbies.  I lost my wire 1/2 square for 40m when a tree fell through it, so it would have been nice to get the phased ones up.  Maybe next year.  If I don't move and put up everything for auction.  That's a different story though not related to the 'blog.  But it's sad.. I'm getting upset that I never have time for anything fun anymore.  I'll mention this once and try not to use the excuse I'm too busy anymore but it has been the truth.

The TS-590S I bought at Dayton has had ZERO transmit time on it.  And maybe a couple hours of RX.  BOGUS AND SAD!


I also started to gain some weight after hitting "bottom" with the gastric bypass.  It became obvious that I'd need to start working out to go from a "stick" (literally, people were telling me that I was looking bad) to at least gaining some inevitable weight back as muscle.  Okay, they *tell* you that 30-minutes of exercise a day is enough.. but it's not... really 4-5 times a week for about 1.5 hours at a time is what I found I need to benefit from it.

Rockwell Collins Rec Center Zagrata 5K 9/2011

But that's, what?, 8-10 hours a week less to do building and operating.  But it sure beats going back up to 350 lbs, .... that is for sure.

I even missed the Iowa QSO Party today because I couldn't get home early enough on Friday not to be exhausted with the 9AM start and everyone else in the family had other plans.  Only in Iowa would someone think that running a contest from 9AM to 6PM  on a Saturday was a good idea.  Hell, it would have been nice to have some after dark 40m/75m contacts, right?  I work 8AM-7PM during the week.  It's not fun to do that on Saturday.   If it would have been 9AM to 9AM or noon to midnight or something logical I would have done it.  But by the time I got home, and then got to bed at 3 AM I couldn't do the 9AM-6PM thing.. oh well.  I suppose the 3AM thing was my fault but as it is it was for a good cause..  I started on it well after 10 PM but I actually had the enthusiasm to do so for the first time in months.. maybe ham radio isn't over for me after all.

So maybe someone who has their crap together much better than I do can tell me how you can be a productive working age adult ham operator and work full time+, have four kids, a wife, and have to work out?  I don't want to quit but I starting to think I have to.  I now understand why ham radio is becoming a "retiree's" hobby.

Anyway, why was I up to 3 AM?  I received a care package via "Royal Mail"  on Friday.. and it's something that was designed almost the same way (actually more clever in many respects) that I had been thinking of doing for close to 10 years.  

British Amateur Television Club "DigiLite" DVB-S serializer and modulator, top side 3/4 done

Bottom side, probably more than 3/4 done

Anyway.. one comment of pride:  I haven't yet ordered parts for this board.  About a year ago I started to buy parts kits from (mainly China and Thailand but) all over and stocked up modern useful parts for a fairly low cost.  Needless to say I have the board 3/4 done from my parts kits.  I did identify an issue where I need to stock chip tantalum capacitors or chip electrolytic as I have had more than one case of not having them when I needed them.  Okay.. I cheated slightly in that I paralleled a couple of 0805 capacitors to make an equivalent of the called for 1206 value.. and I used 0805s for most of the capacitors (which fit) since it's easy to get good quality kits of 0805's from Sure in China but no one has or normally uses 1206/1210's in industry so you won't see cheap kits on e-bay.  I think I was lucky to find a US source for a 1210 chip resistor kit (which ultimately was from China).

Chip resistors are typically less than 1 cent bought that way.  Newark wants upwards of 15 cents/ea for one.  It makes sense to stock up on chip components for the coming apocalypse -- it's typically cheaper to do so than to order specifically for one project!

Chip caps, too.. maybe slightly over 1 cent.  The 0805 0.1 uF caps I bought a "lifetime" roll of 1000 of them for $20 delivered from China.. they are name brand and are good quality, too.  The "Sure" caps are of OK quality but at low RF levels and low DC levels they are perfectly fine.

 The DigiLite is based on the "Poor Man's DATV" by F4DAY.  The project has been updated for modern computers by using a 2 channel FTDI USB serial port chip (which is the "why didn't I think of it?" part of the design) and a closed-source (unfortunately) DSPic33 and Windows PC software to capture data from a "e-bay special" several year old Hauppage PVR-150, 250, 350 (and probably PVR-USB2) analog capture card.  Which are cheap now (about $30 for US NTSC) on e-bay since they only have analog tuners, and many were pulls from OEM PC equipment.  What is special about them for this project is an Conexant MPEG-2 encoder hardware chip.  Newer computers will soon be able to do MPEG-2 and H.264/AVC MPEG-4 in their CPU hardware, so these older chips for now are the only cheap way of easily and quickly doing digital video for this system.  Actually.. I wish there were hardware H.264 encoders out there for a reasonable amount.. but likely there will not be except for embedded stuff because the PC's will handle it in real time without the ASICs.

The BATC's solution of using an inexpensive PIC and the FTDI serial interface is a maybe slightly kludgy but awfully clever solution of inexpensively and simply pumping data to the QPSK modulator chip.  Coming up with an exact kludge like that kept me from this project for 8+ years.  The only disadvantage to it is that they can only do Symbol Rates (SR) up to about 6250Ksym/s.. but for ham use at this time.. that is more than enough!  It's an awesome start!

The modulation used is DVB-S, which is the older digital standard used by most of the world for satellite transmissions.  I've been playing with LEGAL Free-To-Air satellite for many years.  The majority of what is left unencrypted on C-band and Ku-band FSS satellite is receivable on an inexpensive (from $30 used DVB-S to $130 new DVB-S2 high definition PVR type units) set type box and/or PC receiver card.  This same receiver can take in 950-2150 MHz signals as an IF (with a converter and/or a LNA in front of the IF) in Amateur use.

The disadvantages to DVB-S for ham radio is that it is QPSK with Convolutional Encoding and Reed-Solomon FEC..  Meaning that it's about 3 dB "weaker" than the more "modern" BCH/LPDC codes used in DVB-S2 and that it's QPSK -- optimized for weak signals, but pretty weak when it comes to handling multipath.

Current Analog NTSC AM TV doesn't handle multipath well either ("ghosting").. so those who already do ATV are using Yagi beams other directional antennas for their front-to-back and front-to-side directivity more so than the secondary benefit of gain.  Experiments with DVB-S for terrestrial Amateur TV/Data links show that the same antennas work to fix many of those issues.  Hams will likely use beams at these power levels anyway.

One great advantage to DVB-S for ham use-- and overwhelming one in my opinion is that the bandwidth and data rates, even the video and audio coding the the MPEG-2 Transport streams are pretty much completely up to the link user.  DVB-T in Europe and ATSC in the US is only setup for 6/8 MHz channels and IMHO there is no reason for hams to use this much bandwidth in 2011 for ATV.

Experiments by the BATC and others show that the digital signal is much more usable and stable than equivalent bandwidth analog ATV and it just gets better with reduced bit rates.

They seem to do okay with D1-ish video quality (PAL is 625 lines so it's already "more HD" than NTSC) at 1.5 MBPS-2 MBPS with 1/2 FEC for a net of 1.5 - 2.0 MHz of bandwidth.  I will argue that eventually even this simple modulator could be redone to do the more modern DVB-S2 standard, with more advanced audio codec (more compression) and H.264/AVC type data.  We are not far off of that.  I could see with DVB-S2 and H.264 that 1 MHz wide studio SD (D1) could easily be possible and to boot the C/N ratio to decode these signals can almost be 3 dB less, or even more advanced modulation like 8-PSK could be used to further reduce the bandwidth for a 4dB or so hit over Mpeg-2/DVB-S.  Is it possible for 500 KHz FS video?  Probably but the consumer grade Set-Top-Boxes might not be able to support it.  Most can be coaxed to do 2000 Symbol rate or even 1500... I've heard of some doing 1000.

Ho, Hum?  ATV?  who cares?  Well.. see.. it's not really just that, is it?  The data on DVB-S is transmitted as  as Transport Stream (of 188 byte packets) but there are protocols such as DVB-IP that can do internet over DVB modulation.  There are $20 e-bay boards capable of receiving this as a native computer network interface.  If we can write a data driver to go the other way... half and full duplex multi megabaud links could be done for the price of a Digilite and a TwinHan or SkyStar (or even cheaper like old Broadlogic) DVB-S cards and the supporting RF amplifiers and preamps.  That would have to be a boon for things like emergency communications... and maybe even getting a packet radio network up again.

Oh, and supposedly the newer FET based Mitsubishi power modules seem to be much more linear than the older Mxxxxx series bipolar modules.. so generating a few watts of linear PSK seems to be quite doable for reasonable cost at 70cm (but is it legal in the US?  Our OUTDATED data rules on that band seem to say no even though bandwidth can be reduced by a factor or 6-8 for more reliable digital signals!), 902-928 MHz, 1240-1300 MHz and probably even beyond.

So this is the start of an interesting project for me that I've wanted to do forever.  Hopefully it will turn out well and can be revolutionary.

The bad thing here.. is going back to the rant.. the other project from last year will have to stay in it's current state a little longer.

Summer Blues

Just a quick post to verify that this blog is working.  I can't seem to comment on a comment on another page.

I am going to get back to posting at least once a month here and/or at Amateur Radio.com

Summers are pretty tight for me anyway (I do have a XYL and four young kids remember).. but I had storm damage this summer that also made me go QRT.  I'm starting to catch up.  I"m about at "the end of June" now.

I will be back and the projects that seemingly got abandoned in May will start back up.  Until then... 73

The value of knowing what you are doing...

...and double checking everything even when you might not otherwise think it is necessary...

Well.. I spent a small fortune on ham radio in the last two months or so.  One purchase is a new TS-590S and the other... well...

I bought a used TL-922A that was in very good cosmetic shape about three weeks ago.  Didn't have time to fire it up until today.  It has new RF Parts 3-500ZG tubes, AG6K suppressors... and well it had a 160m "improvement" mod done to it.  I paid good money for it.  Enough that I'm almost embarrassed to say, depending on how this all turns out.  Cosmetically 9/10.. Good power out for the 3/4 hour or so.

Now I hope it still has a functional HV supply.  I am wondering if I have another SB-200 that I finally got everything shaken out of right before buying the TL-922.  (Took 9 years.. but then again, it was a cheap amp to start off with...)  It was putting out 1000-1200W on all bands I tried (as it is supposed to) with about 85W of drive.... 80m/75m, 40m, 20m... 15m  *POP*

eek...crapola.. that was a lot of $$ that went up in smoke...

Here is the culprit:

Okay.. the guy doing the mod did nice clean work.. HOWEVER.. one cannot bypass (the glitch resistor too! I hope the HV is ok...!!!) the plate supply, which is 3.1 KV (SSB) on the TL-922 with a 0.005 uF 3 KV disc!!!  (The other end was attached to the interlock mounting screw for ground with longer leads than I would have liked as well.)   I suppose if that is a major improvement on 160m and 80m that I can add about 5000 pF with another 7 KV+ DOORKNOB cap.. but this addition made the amp pop and go boom within about 45 minutes of when I first turned it on.

Unfortunately that cap is now a 55 ohm resistor and it did take out one of the two "Bussman" FNM-15 time delay fuses.  I'm keeping my fingers crossed that the supply can take it.  The interlock is there also, but it's still a frightening proposition when something like this happens!

Of other interest, and I am going to e-mail Rich Measures... it appears that the resistors in the suppressor kit (which are bypassed with the nichrome wire and getting a little discolored.  I don't know if that is because of the cap venting out (it is possible) or there is something else wrong.

See the suppressors look like they are installed correctly (according to what I've read on the web), however the ones that are bypassed with the nichrome coils seem a little discolored at the ends.  I am gong to e-mail the designer of these suppressors and see what he has to say about that.  

Anyway.. it's starting to be that sort of weekend.  The TS-590S seems pretty impressive and I am looking forward to running it with this amp.. but maybe I'll be out over $1K (I said it) and will have to use the ugly SB-200 with it instead.

Sigh..

From a physical check of the unit, it all else seems good (no smoked parts).. so once I can get over to the local Grainger store to get this oddball fuse, I am *hoping* I can fire it back up.

Anyone else want to comment on the extra 0.005 uF... should I start digging for a doorknob to add to the amp, or was it a stupid "improvement"?

Needless to say.. the moral of this story is do not parallel or replace a doorknob with a disc!  Do not put a 3 kV disc in a 3.1 KV DC circuit with over 100V of AC injected on it.  sigh...

Other 'blog and Spring "slowdown" -- Shameless begging

Sorry I've been so quiet lately.  I've had an over month long stint of 50+ hour weeks at work, a lot of stuff to do with the kids, and I also got invited to post at a more general interest Amateur Radio 'blog.  It is my intent to still post here-- with more details on my projects-- but I will do more general interest and synopsis type stuff at the other site.  Weather in IA is only good about 5 months a year, and I have to do outside stuff starting now, or stuff will fall apart around me-- more than it already is!

See AmateurRadio.com for some of my other posts.  I may cross post some of the stuff, but since the interfaces between the two sites are a lot different, that may be too time consuming.  (The other site's "wordpress" interface stinks, IMHO.. but it is what it is!)  I invite anyone interested in my drivel to look at the other 'blog as much of it will be more interesting than my (highly biased!) thoughts on the hobby.

I have a lot of stuff in the works, if and when I get it done (if and when I ever have free time again to work on it).. there will be flurry of postings at both sites, and hopfully completed projects will go to the website.  It takes a long time to properly document the projects, but there are inherent advantages to doing so.. so I intend on 'blogging the results.

Projects still in the works:

The HF amplifier project, and SDR-Cube to "general purpose HF rig".  This is the long term one.  The AN-762 Amplifer is done minus the finals being mounted.  The K5OOR amp filter is done, but I still want to bring it into work and tweak the filters on a VNA.  Then I need to interface it to the AVR and write a little code to idiot proof the operation of the Amp.

Antennas:  18 MHz/24 MHz WARC beam made from a Cushcraft 10-3 and other surplus antenna tubing I had lying around.  This is almost done, but needs to be tuned.  It should be a useful writeup when I get it done.  It's a "Moxon" (Cebik) Rectangle on 17m and a two element "open sleeve coupled" (coupled resonators is a better name) two element yagi on 12m.

Antennas: 6M beam on the same mast.. a 30m dipole either rotatable on the same mast or as a wire from the roof tower (6M and WARC) to the main tower.  Of course the roof tower needs to have a rotor put into it, a thrust bearing mounted and it be bolted to the roof of the garage opposite to the main tower...

Antennas:  two element phased array for 40m.  I have new tubing from DX engineering for this and was hoping to have posts in the ground by now.  I think I'm going to elevate the radials since it's probably already too late to lay them down and have the grass grow around them this spring!  :O(.. I can always add a screen under the elevated ones later.  On 40m I don't think it's so critical.. 80m and 160m you probably cannot elevate the antenna enough practically to make the elevated radials work worth a darn.  I have my own theory on this but can't prove it so I may never mention it.

and.. I have a shed kit to build to get the mower and snowblower out of the garage to try to make up some room that I took away when I put my hamshack room in the detached garage by the antennas.

Operating:  Still working on DXCC (only have 41 confirmed out of about 120 countries worked for ARRL, less on eQSL.cc..)  I just got envelopes and foreign stamps from William Plum and some IRC's from the post office, so the $6 per country cost to get mail QSLs is starting.  Cocaine is a cheaper hobby, methinks..  Also working on WAS.  I could use some help with this.  If you are in KS, RI. ND, SD, MN, ME, NV, WY and are willing to QSL LoTW or paper I can use you (also eQSL.cc would be highly appreciated too).  If you are in LoTW and in DE, UT, MT that's easier than the card checker!  All skeds can also be arranged to get/contact a Collins ARC card (quite collectible-- very nice) because I can also contact you as W0CXX.  I'm also willing to do this from a vintage Collins radio as well if it's near working hours in the midwest.  Contact me via e-mail via my QRZ.com listing e-mail.  This offer also goes for *any* DX even if it's something I already have confirmed.  I'll do it for any stateside as well... :)

So it'll be a busy spring.  I appreciate the followers of this 'blog being patient.  Hopefully I'll get it all done and have some good posts upcoming.

73