logic Analyz

108 Pages·2015·10.34 MB·English

HOW TO REPAIR CD PLAYERS
MARCH 1998
Build aNigh- Perfamma,ce
logic
Analyz
Capture up to 40- million
samples a second
Maintaining Your
Own Personal
Computer
These simple steps can keep
-and
your computer your
-in
data the best of health
Build a "Nome -Brew"
Temperature
Controller
A "must -have" accessory if yoc
make your own beer or wine
Restoring a #EM4E1.34F.x.x:.x:.x.x:.x 77-±)IGI1- 21046
#DHM5515R093 7#4Ei.1734 OAP 19
Reel Recorder S4,50 U.S.
S4.99 CAN.
Bring that golden olcie ROBERT DARM APR 99
back to life 3315 RED RAIN PATH 92EN
COL U M e F A ND 21046-2077
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1 www.americanradiohistory.com
Electronics
NOW
Vol. 69 No. 3
CONTENTS
998
MARCH
1
ON THE COVER TECHNOLOGY
23 PROTOTYPE
Miniature
33 BUILD A HIGH - PERFORMANCE LOGIC ANALYZER umanned
aircraft, a
If you've done any amount of digital- circuit trouble- radar
flashlight,
shooting, you no doubt know how valuable an instrument
analyzing
a logic analyzer can be. But if you've ever shopped for blood
an analyzer, you also disorders, smartcard ICs, and
HOW TO REPAIR CO PLAYERS
know how expensive ni MAO UM more.
a top -flight unit can be. 44 MAINTAINING YOUR OWN PC
Yes, there are a num- ype These simple
ber of lower -cost PC NM a Ritlr-hrronmwse steps can
add -ons that can be Logic Anal ensure the
CidY w te 4(Hilles health of your
bought or built, but swiss s asaib personal
Maintaining Your
most have limitations; Own Personal computer and
either they have a low Cm,o,,m,,mpou,.t er your valuable
1m4a1a -, m.Ims. ,h.,am1a1,1 - data.
sampling rate or have RTaelma. paegmra.-teu re Stephen J. Bigelow
only a few sampling Controller
channels. That is until Amaaero. nr. nMr wmm" na ,rs.e.nr nar ya ins r nn 51 RESTORING A "REEL"
Reavipa
now. This month's Reel Recorder RECORDER
This month
cover story introduces we show you
a PC -based logic analyzer that features a 40 -MHz the first steps
maximum sampling rate-, 1 6 channels, and more. Even in bringing
your cherished
better, it's expandable. Robert G. Brown treasure back
-
to life.
Phil Van Praag
As a service to readers, ELECTRONICS NOW publishes available plans or information relating to newsworthy products, techniques and scientific and technological
developments. Because of possible variances in the quality and condition of materials and workmanship used by readers, ELECTRONICS NOW disclaims any
responsibility for the safe and proper functioning of reader- built projects based upon or from plans or information published in this magazine.
Since some of the equipment and circuitry in ELECTRONICS NOW may relate to or be covered by U.S. patents, ELECTRONICS NOW disclaims any liability for
the infringement of such patents by the making, using, or selling of any such equipment or circuitry, and suggests that anyone interested in such projects consult a
patent attorney.
ELECTRONICS NOW, (ISSN 1067 -9294) March 1998. Published monthly by Gernsback Publications, Inc., 500 Bi- County Boulevard, Farmingdale, NY 11735-
3931. Periodicals Postage paid at Farmingdale, NY and additional mailing offices. Canada Post IPM Agreement No. 334103, authorized at Mississauga, Canada.
One -year subscription rate U.S.A. and possessions $19.97, Canada $27.79 (includes G.S.T. Canadian Goods and Services Tax, Registration No. R125166280), all
other countries $28.97. All subscription orders payable in U.S.A. funds only, via international postal money order or check drawn on a U.S.A. bank. Single copies
$4.50. © 1998 by Gernsback Publications, Inc. All rights reserved. Printed in U.S.A.
POSTMASTER: Please send address changes to ELECTRONICS NOW, Subscription Dept.. Box 55115, Boulder, CO 80328 -5115.
A stamped self- address envelope must accompany all submitted manuscripts and /or artwork or photographs if their return is desired should they be rejected. We
disclaim any responsibility for the loss or damage of manuscripts and/or artwork or photographs while in our possession or otherwise.
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MARCH
9 9 8
1
BUILD
T H
I
Hugo Gernsback (1884 -1967) founder
59 BUILD A "HOME- BREW"
TEMPERATURE CONTROLLER LARRY STECKLER, EHF, CET,
One key to making your own Editor -in -chief and publisher
beer and wine is precise ADRIA COREN, Vice -President
temperature control, and this KEN COREN, Vice- President
-
unit makes achieving that a EDITORIAL DEPARTMENT
snap. David W. Boertjes CARL LARON, editor
JOSEPH J. SUDA, technical editor
JULIAN S. MARTIN, associate editor
EVELYN ROSE, assistant editor
TERI SCADUTO, assistant editor
MICHAEL A. COVINGTON, N4TMI
17__;j\ii\rL=
contributing editor
I SAM GOLDWASSER, service editor
JEFFREY K. HOLTZMAN,
computer editor
FRANKLIN J. MILLER,
audio editor
13 EQUIPMENT REPORT DON LANCASTER,
contributing editor
RadioShack Accu Weather
DEBBIE CYBULA, editorial assistant
personal weather station..
ART DEPARTMENT
ANDRE DUZANT, art director
RUSSELL C. TRUELSON, illustrator
10 COMPUTER CONNECTIONS
- PRODUCTION DEPARTMENT
Pilot graphing, Small C, e -mail, RUBY M. YEE, production director
and more. Jeff Holtzman KATHRYN R. CAMPBELL,
production assistant
KEN COREN,
desktop production director
18 SERVICE CLINIC LISA BAYNON, desktop production
Servicing CD players and CD- MELISSA GIORDANO, desktop production
-RO M drives. CIRCULATION DEPARTMENT
Sam Goldwasser THERESA LOMBARDO,
circulation manager
GINA GALLO,
circulation assistant
27 AUDIO UPDATE REPRINT DEPARTMENT
Using- t he capacitance- substitution MARIE FALCON, reprint bookstore
box. Franklin J. Miller
Typography by Mates Graphics
Electronics Now is indexed in Applied
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Interactive Car Navigation System Temperature Logger
The low -cost data- logger family
from AEMC is unique because they
require no user set up and are able to
automatically adjust the scale and sam-
ple rate to optimize to the recording.
The Simple Logger, a temperature log-
ger, has recently been added to this
family.
One -button operation makes the
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use. Temperature inputs can be done
either through an internal thermistor
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unit is directly compatible with indus-
try- standard 10,000 -ohm thermistor
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Easy to install and use, Philips Car display. They can choose from various
Systems' CARiN 520 expands consumer options, including a male or female voice
access to digital vehicle- navigation tech- in one of six languages; an optional flexi-
nology that previously was available only ble stalk mount, which allows placement
through luxury automobile accessory in several locations within the vehicle;
packages. Including a navigation compit- and background monitor colors that can
er, LCD monitor, remote control, and be changed from orange -red to green to
installation components, the system can blue.
be installed by a professional in as little as CARiN 520 is controlled by an illu-
CIRCLE 21 ON FREE INFORMATION CARD
two hours. minated IR remote that may be handheld
CARiN's easy -to -use remote and or permanently mounted. A personal - Included with the logger is Windows-
route selection, automatic alternate rout- destination memory can store up to 100 based software, which allows plotting, sta-
ing, CD -ROM mapping, and emergency addresses; the most recent 10 addresses tistical analysis, text annotation, and zoom
features combine into an accessory that are stored automatically. Seven U.S. capability. Graphs and tabular listings can
makes driving safer and more enjoyable. regional CARiN CD -ROM maps are be printed, or the graphs can be pasted
The Philips system is one of the only sys- available. directly to the Windows clipboard for
tems employing dead reckoning as its pri- About the size of a vehicle CD player, insertion into other programs. Stored files
mary navigational tool. Dead reckoning the navigation computer is sufficiently can be imported by all popular spread-
uses an integrated gyroscope and patent- compact to mount under the rear deck, in sheet, datasheet, and word processing
ed CD -ROM database to pinpoint the the trunk, beneath a seat, or on the floor programs. The Simple Logger stores over
vehicle's location, and then checks itself of the cargo area. The CARiN 520 retails 8000 data points, and the device has a
with the Global Positioning System for $1999, plus installation and CD- built -in RS -232 port for downloading.
(GPS) for accuracy. That method elimi- ROM mapping. The data logger's compact size (27/8 X
nates problems caused by interference in Philips Car Systems 25/8 x 15/16) makes it easy to take any-
places such as urban canyons or when a 64 Perimeter Center East where. Depending on the model, it is
user is caught between satellite links. Atlanta, GA 30346 -6401 priced from $149 to $159, with the soft-
Drivers receive both visual and audio Tel: [phone] ware and the interface cable included.
directions through a five -inch LCD color Fax: [phone] (Continued on page 22)
3
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Accredited B.S. Degree in
111111WINN; ;J
Computers or Electronics
by studying at Home
Grantham College ofEngineering EhLX
offers 3 distance education programs:
B.S.E.T. emphasis in Electronics
B.S.E.T. emphasis in Computers
B.S. in Computer Science
The Uncertain Face of TV
ClrElectronics Workbench Professional 5.0
t `included in our B.S.E.T curriculums The buzzword at this year's Consumer Electronics Show (which will have passed by the
-Approved by more than 200 Companies, time you read this) is'slated to be DTV, or digital television. That's because manufacturers
VA and Dantes, (tuition assistance avail.) will be unveiling their first products for the new digital broadcasting standard at that show.
For your free catalog of our programs dial
1- 800 -955 -2527 For those of you who haven't heard about it, or didn't read my Editorial last July ( "The New
Face of TV"), DTV is scheduled to completely replace the existing NTSC broadcasting
http: / /www.grantham.edu standard by 2006, with the first digital broadcasts to begin this fall. Yet, with all this impend-
ing activity and change, no one is really sure what shape DTV will take.
GCE
Many assume that DTV automatically means HDTV It doesn't. Another poisstib le use of
Your first step DTV- and the increased bandwidth broadcasters received to accommodate is multi-
to help yourself casting: breaking up the signal into multiple standard -definition TV channels.
better your future!
The problem for broadcasters is that regardless of which way they go, DTV is going to be
Grantham College of Engineering an expensive proposition. Costs for converting each station is estimated at between $2 and
34641 Grantham College Road $14 million dollars. And no one is quite sure if those costs are going to be recovered in the
Slidell, LA 70460 -6815 short term regardless of the type of DTV broadcast. Some station owners are even won-
dering if it makes any sense for them to stay in business at all.
.........-
Remember that almost all station revenues are derived from advertising. Will advertisers
Some Say Watching Tropical be willing to shell out extra dollars for their spots to run in HDTV? Without sufficient
Fish Lowers loorl Pressure advertising, will stations be willing or able to broadcast a significant amount of HDTV
IL material? If there is limited or no programming, will consumers spend the $3000 or so that
Relieves Stress...
the first -generation HDTV sets might cost? And, if there are few sets in the hands of con-
sumers, will advertisers be willing to have their spots air during HDTV broadcasts at all?
If broadcasters go to multicasting, where will they get the programming to fill the extra
channels, and what will they have to pay for it? The thought of premium subscription se-r-
vices has been tossed about, but the political backlash that such a use would generate
remember, the stations received their extra spectrum at no charge -likely makes that pos-
sibility a remote one for the time being.
They Could Be On To But even free multicasting faces opposition from some quarters. In fact, this past fall
Congress grew livid when some networks and broadcasters indicated that the multicast-
Something.
ing approach might be the way to go. During hearings, the reaction was so strong that
executives were forced to backtrack somewhat on that possibility.
To illustrate how much confusion and uncertainty exists, at those same hearings FCC
Chairman Hundt went on record to say that he felt that multicasting offered a good use of
the spectrum as it would offer a free and viable alternative to cable TV
In short, the only thing certain about DTV is uncertainty. We'll keep you posted.
Discover the Carihhean aboard a Tall Skip.
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For more information call your travel agent
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Windjammer
Carl Laron
Bar ufout'cr uises Editor
4 Y.O. Box 190120, Dept.3369 Miami Reach, FL 33119
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The Microcontroller -a
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in everything from and Appendix III provides vendor infor- Internet, and how it can be made more
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5
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O&A
READERS' QUESTIONS, EDITORS' ANSWERS
As you've discovered, regenerative re- removing C2 and R2, and make sure C3,
Regenerative Correction
ceivers are very sensitive to power -sup- C4, C6, and R3 are as close to the chip
ORegarding the regenerative AM radio in ply coupling. For best results, power the as possible.
the July 1997 installment of "QbA" (on receiver from one battery and the audio Because of its low- impedance input
page 8), shouldn't the transistor be an amplifier from another. If that's not pos- and bridged output, the MC34119P
NPN? The diagram shows a PNP. Also, sible, you can try isolating the two cir- might be a better choice for this applica-
what gauge of wire should LI be wound cuits as shown in Fig. 1. There are two tion. Figure 3 shows Motorola's recom-
with, and what is the length? -W ould a 250- bypass capacitors on each side because mended circuit. For best results, use a
µH ferrite bar coil work? Pete Haas, large capacitors aren't efficient at high 32- or 64 -ohm speaker.
Kent, OH frequencies.
Also, the LM386 itself is prone to
A You're right- the 2N3904 transistor is oscillation at radio frequencies, and the
an NPN even though the PNP sym- LM386 circuit that you sent in (shown EPROMS Demystified
bol appears in the diagram. (Your author in Fig. 2) looks like it has too much gain. Q1 am new to electronics and would like
does his own drafting and can't blame Regenerative receivers themselves have to learn more about EPROMs and
anybody else for this one.) The coil is not tremendous gain and don't need much EEPROMs. Do they program through a lan-
critical; we used 36 turns of No. 28 mag- audio amplification after them. Try guage, or does the- us er have to plot the actual
net wire close -wound on a 4 -inch spool internal wiring? G. G., Bradenton, FL
that had originally held gift-w rapping
ribbon. Any high -Q coil of about 250 pH +9V IN A Let's distinguish three different
should work just as well. devices: (1) ROMs (read -only memo-
ries); (2) microcontrollers, which are
TO 3R3I0 R472 TO one -chip computers that include some
Regenerative R4 CVR _ IlAM P finoprmut -oofu RtpOuMt p, otrotsg; eatnhde r (3w) itphr oCgrPaUm manad-
Troubleshooting 0C.0l 11 10 Cµ2F T+ C2230 C4 ble logic devices (PLDs), which are
µF arrays of gates whose interconnections
QI tried using an LM386 audio amplifier can be programmed by the user.
with the regenerative receiver presented ROMs, or read -only memories, sim-
in July, and it started "motorboating" and FIG. 1- HERE'S HOW TO POWER both ply store information. A ROM chip has
displayed all sorts of spurious oscillations. your regenerative receiver and an audio sixteen to twenty address inputs and
Could you provide a simple circuit to drive a amplifier from a single supply. eight data outputs. Information is repre-
speaker from the regenerative receiver by
means of an LM386 or an MC34119P?
And, if possible, I would like to see a REMOVE C2 + C3 +9V
schematic of a simple superregenerative 101.¡F 220
receiver to receive aircraft -fre quencies Cl +IC µF Io?:1 (= C3, C4
(C1a1n7o -g1a3 P6a rkM, HCAz) . Thanks. L. H., AUDIO 4µ.F7 8 IN FIG. 1)
IN
4 +I( IC1
LM386
ATaking the easy question first, plans C6 C5
for a VHF superregenerative receiver R1 7 0.01 100 SPKR
10K 8.12
are given in the ARRL Handbook for VOLUME PLF
Radio Amateurs, 1998 Edition, together - R3
with an explanation of how it works and - C7 + R2 1052
the special "ugly bug" construction 10 µF 270K PLACE CLOSE
technique required. You can get that ADD IF ../v TO IC1
_
book from the American Radio Relay NEEDED REMOVE
League, Newington, CT 06111. FIG. 2 -FOR USE WITH A REGENERATIVE RECEIVER, the modifications shown to the
Now for the motorboating problem. reader's circuit will greatly improve stability.
www.americanradiohistory.com
address inputs, the data stored at the M2L Electronics (3526 Jasmine #4, Los
oca- corresponding location appears on the Angeles, CA 90034; Web: www.m21.
t°es
atsati;ae05p1e, eight output lines. It could be any bit com), and the Pocket Programmer from
xSl Js 4cdress pattern whatsoever. Intronics (Box 13723, Edwardsville, KS
ROMs are usually used to store pro- 66113); both are priced under $200. In a
)áac ;e0rdres°s, grams for computers, but they have higher price range, the Needham's EMP-
r0
Seos e be dv O01\ Otoi 0ee 04 e rtod atthae. stohme ea dodtrheessr luinseess taos aw beilnl.a rByy c ocuonntneerc, tyinogu 2av0 ai(laabboleu t $fr4o5m0) gGeetsn egroaol d Dreevviiecwes . IInt's-
0 Ol.O °°s can step through all the addresses in struments; Te1:408- 241 -7376; Web:
OOO Qve°0'S¡° Sotes v sequence. You could use the output to www.generaldevice.com.
N OG4aò 0 C ' p NCDAEPD; ) pmreosdsuacgee s pina ttMeronrss eo cf odbeli. nking lights or artiTcloe sl eianr nt hme oNreo vabeomubt eRr O19M95s , siseseu et woof
\e09 ROMs come in several types: mask - Electronics Now, "Low Cost EE-
programmed (programmed at the fac- PROM Programmer" and "Five Easy
tory), OTP (one- time -programmable, EEPROM Projects;" reprints are avail-
which means you can program them able from the Reprint Bookstore (see the
but not erase them), EPROM (erasable sidebar "How to Get Information About
with UV light), and EEPROM (electri- Electronics "). See also Experiments with
5
cally erasable programmable read -only EPROMs, by Dave Prochnow (McGraw -
memory). Flash memory is a variety of Hill, 1988).
EEPROM where the whole chip has to The bits in an EPROM don't mean
SPKR
8- be erased at once. anything; they're just stored informa-
640 To program an EPROM, you use tion. If the EPROM is connected to a
your PC to create a file of bits (or of CPU (central processing unit), the CPU
hexadecimal digits that represent them); will read the EPROM's contents and
then download this file into the EPROM interpret it as instruction codes. If the
...A'S MC34119 AUDIO
,nput impedance, making it through a programmer. CPU and EPROM are on a single chip,
with. Note that capacitor C3 is Some good, inexpensive EPROM it's called a microcontroller. To program
acessary. programmers include the EZ -EP from a microcontroller, you first write your
IF
Create and
t 4.8 - C:\PLflB\flMP_BIP.WPF Analyze Circuits
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CIRCLE 122 ON FREE INFORMATION CARD 7
www.americanradiohistory.com
HOW TO GET INFORMATION ABOUT ELECTRONICS
On the Internet: See our Web site at Periodical Literature, available at your public .,ff p
http: / /www.gernsback.com for information library. Copies of articles in other magazines We Q,
and files relating to our magazines (Elec- can be obtained through your public library's toys.
tronics Now and Popular Electronics) and interlibrary loan service; expect to pay about ment to pr.
links to other useful sites. 30 cents a page. ordinary o
To discuss electronics with your fellow state device i'ro
enthusiasts, visit the newsgroups sci.elec- Service manuals: Manuals for radios, TVs, gered? I couldf`z co
tstercouin.re.ichleso.cmrtereopbanriierc,ws ..d sec"sFi.ioegrln e,c staraolnend"i csmr.ececos.msraapdgoieons.ae mnatasre-, VeCrCos.R , asr,Ie n adauiavdnaioail apeboqlleuis ip,f rmoIemNn t,H 4a6on2wd1a 4rsd o mW(1e-. 8 Sc0oa0mm -4ps2 u8t&-- aH .t aDlk. inKg, bPurhgihlas: a0z,- 'e' Q1, "b 4r'.s 4"
permitted only in rec.radio.swap and 7267). The free Sams catalog also lists AVoice- recordinK,,. .
m isc.industry.electronics. marketplace. addresses of manufacturers and parts deal- are as close as yc
Many electronic component manufac- ers. Even if an item isn't listed in the catalog, store. For example, tI
turers have Web pages; see the directory at it pays to call Sams; they may have a sche- up to 20 seconds of au
hestt ps:u // cwhw aws. hhitttepx: /./ cwowmw/ c.hti.ipcodmir/ , aonrd t rhyt tap:d /d /wrewsws.- matMic aonnu afillse wfohri cho ldtheer y tceasnt ceoqpuyip mfore nyto ua. nd dagivei diesd innotno- sveovleartialle -mteha(
motorola.com (substituting any company's ham radio gear are available from Hi lose its memory when poi
name or abbreviation as appropriate). Many Manuals, PO Box 802, Council Bluffs, IA special programming eq
required; audio amplifiers
IC data sheets can be viewed online. 51502, and Manuals Plus, PO Box 549
recording and playback are on
Tooele, UT 84074.
Books: Several good introductory electron- These chips are made by Info.
ics books are available at RadioShack, Replacement semiconductors: Replace- Storage Devices (ISD), Inc.,
including one on building power supplies. ment transistors, ICs, and other semicon- Hamilton Ave., San Jose, CA 9512.
408 -369 -2400; Web: www.isd.com.
An excellent general electronics textbook ductors, marketed by Philips ECG, NTE,
is The Art of Electronics, by Paul Horowitz and Thomson (SK). are available through can view data sheets online at their d
site and learn more about their product
and Winfield Hill, available from the publish- most parts dealers (including RadioShack
er (Cambridge University Press, 1- 800 -872- on special order). The ECG, NTE. and SK
7423) or on special order through any book- lines contain a few hundred parts that sub-
store. Its 1125 pages are full of information stitute for many thousands of others; a REI Emergency
on how to build working circuits, with a mini- directory (supplied as a large book and on
mum of mathematics. diskette) tells you which one to use. NTE ti bly neighbor's CB izztelferes with my
booAk lsfoor inRdaidsipoe nAsmaabtleeu riss , Tchoem ApRrisRinLg H 1a0n0d0- anruem dbifefersr eunst.u ally match ECG; SK numbers ers,c oardnleds s epvheonn e-,n erw eg umlaurl tpimhoendei,a T Vsp esapkeearks.-
pages of theory, radio circuits, and ready- to- Remember that the "2S" in a Japanese What can I do? Name withheld
bRuailddi op Rroejleacyt sL, eaagvauiela, bNlee wfrionmgt otnh,e CATm 0e6r1ic1a1n, tmypaerk endu mDb9e4r5 isi su asuctaullayl lyo ma it2teSdD; 9a4 5tr. ansistor A If only one piece of audio equipment
and from ham -radio equipment dealers. were receiving interference, we'd sus-
pect the problem might be on the receiv-
Hamfests (swap meets) and local orga-
Copies of past articles: Copies of past nizations: These can be located by writing ing end. There is, unfortunately, no law
articles in Electronics Now and Popular to the American Radio Relay League that requires stereos, TVs, or telephones
Electronics (post 1993 only) are available (Newington, CT 06111; http: / /www.arrl.org). to block out radio signals, and some of
them are shoddily built.
from our Claggk, Inc., Reprint Department, A hamfest is an excellent place to pick up
The fact that you're getting interfer-
P.O Box 4099, Farmingdale, NY 11735; Tel: used test equipment, older parts, and other
ence in so many different pieces of equip-
516- 293 -3751. items at bargain prices, as well as to meet
ment strongly suggests that the problem
Electronics Now and many other maga- your fellow electronics enthusiasts -both
is with the transmitter. Your neighbor
zines are indexed in the Reader's Guide to amateur and professional.
may have defective equipment or an
improperly installed antenna, or he may
program in assembly language, C, or tiny fuses) or create (by melting "anti - be running an illegal amount of power.
BASIC; then test it in a simulator on fuses" to make connections). Their main CB is designed for short -range commu-
your PC; and finally download it into advantage is that, because they consist nication, hut, unfortunately, some CBers
the microcontroller with equipment only of gates, they respond to their get a kick out of blanketing North
much like what you'd use to program inputs almost instantly rather than exe- America with their signal, using a 1000 -
EPROMs. Back in January and February cuting instructions one at a time like a watt linear amplifier instead of the legal 4
1994, we published plans for two micro - microcontroller. PLDs are often used in watts. Some people just want to have the
controller programmers. Many com- address- decoding circuits inside com- whole continent to themselves!
mercial EPROM programmers also pro- puter peripherals. There are languages You should call the nearest Federal
gram microcontrollers. for describing the interconnections con- Communications Commission (FCC)
Programmable logic devices (PLDs) cisely. We covered PLDs in detail in the field office; in your case, that's Atlanta at
are arrays of gates whose interconnec- May 1994 issue, including plans for a 770 -279 -4621. The FCC has imposed
8 Lions you can either destroy (by blowing programmer. heavy fines on CBers who nm illegal
www.americanradiohistory.com