Loadingsuccess437

See pictures for close-ups of the shaft holes. Replacing tuner knobs is a simple repair, we recommend these instructions to guide you. Color-matching Cream Parts and Bindings There have always been slight variations in the color of the cream plastic parts used on Gibson and other guitars. It's not uncommon to see brand new and vintage guitars with bindings, pickup rings, toggle switch rings. Yes, usually he is in standard tuning but there's a difference between standard tuning and standard pitch. Since a lot of his songs are pitch shifted, if you wanted to play like the record, you are going to have to tune to a higher pitch. Ex: ode to viceroy is in standard tuning, but instead of 440hz it is 452hz. Tuner Parts - order today with StewMAX FREE Shipping! Apple does a pretty good job of making sure your Mac’s performance is well tuned right out of the box. So there aren’t many single things you can do to make your Mac dramatically.

1: Navigation Bar

•Navigate to https://www.rigpi.net by clicking the RigPi logo or RigPi name.

•TUNER..WEB: opens window.

•SETTINGS: contains a list of settings windows, click the down-arrow.

•Search box: enter call to look up in the FCC database or optional QRZ XML online service. Press enter or click the magnifying glass to look up.

•Exit RigPi.

2: Tuning Knob

•Tap/click the detent and rotate knob to tune higher/lower in frequency. The tuning scale is determined by the underlined digit in the frequency readout of the Frequency Panel.

•Tap/click/hold the plus or minus button to move up or down in frequency. Hold tunes in the same direction at the rate of 2 steps per second.

•Tap/click/ the PTT button to engage the RSS PTT function The PTT button operates in a toggle mode is a toggle. Tap/click again to go into receive.

When using the Macro Decimal mode to control external relays, a row of LED lights appears below the Tuning Knob. Tap/click a light to turn on an associated relay, tap/clik again to turn it off. One slave connection is available for all accounts. If you attempt to connect more than one RigPi will show an alert telling which account is already using the slave connection. A radio must be connected before relays can be controlled.

3: Macro Bank

•128 macros with 4 banks of 32 programmable macro buttons (SETTINGS>Macros). Can be used to send CW, control the radio through Hamlib commands, control the radio through Hamlib 'w' commands unique to the selected radio, and system commands (the system command option is disabled by default). Change the Macro Bank using the Macro Bank button (10) or a custom macro.

4: Status Bar

•Main frequency (shows red when no radio connected)

•Split frequency (shows when radio is in the split mode)

•Mode

•User, user's call and account username

•UTC Time

•Only Main Frequency is displayed in narrow screens

5: Sliders

•Sliders are hidden if your radio doesn't support changing levels by CAT.

•4 sliders are provided: AF (AF Level); RF (RF Gain); PWR (Power Output Level); MIC (Mic Level).* The sliders adjust the radio front panel controls, not the CODECs (if appropriate for your radio) or Mumble.

*If you find your radio is not responding correctly to sliders, analog level reading for that radio may not be fully implemented. In addition, some radios only support several fixed levels for a slider rather than a continuous range. Please post a note on the RigPi Forum to let us know of any problems you encounter.

6: Band and Mode

•Tap a Band button to change bands or a Mode button to change modes. Each band has a memory for the frequency last used on that band.

7: Radio Connection and VFO

•Connect Radio (Green: connected; Red: not connected; Rotating Arrows: connecting)

•Disconnect Radio

•VFO/Memory operations

•See below for details

8: Frequency Panel

When screens are wide enough to display the RSS S-meter, the frequency panel, above, is used.

For narrow screens, where the S-meter is hidden, this format is used.

•Displays the Main and Sub VFO frequencies, band, the current UTC time, operating mode and receive/transmit status.

•A keypad is included to set the frequency of selected digits. See below for all tuning options.

•The Main and Sub frequencies have bars above and below each digit. When a digit is selected the bars above and below the digit are bold. Tap/Click a digit to select it. The selected digit sets the tuning resolution for the Knob and typed digits. Click the lower half of a digit after selection to tune down and the upper half to tune up.

•Change the color theme of the Frequency Panel using Account Settings (SETTINGS>Accounts>Edit). Four options are provided: Orange, Night, LCD, and High Contrast. This setting also affects the S-Meter.

9: S-Meter

•Shows signal strength when in receive and an optional reading when in transmit. There is no way to adjust the calibration of the S-meter. Some radios may not support S-meter and/or optional transmit queries through CAT. The S-meter is not shown on narrow screens. See the Advanced Radio settings (SETTINGS>Radio>Advanced) for more information on the optional transmit readings.

•Change the color theme of the S-meter using Account Settings (SETTINGS>Accounts>Edit). Four options are provided: Orange, Night, LCD, and High Contrast. This setting also affects the Frequency Panel.

10: Accessory Buttons

•Macro Bank to change the displayed bank

•Knob Lock to freeze the tuning knob.

Radio Connection and VFO Buttons

Frequency Tuning

Tuning options allow you to tune both Main and Sub VFO's in many ways.

Push-to-Talk

Several ways to engage Push-to-Talk (PTT) are provided. PTT uses CAT and solid state switches on the RigPi Keyer and RigPi Audio boards. See SETTINGS>Radio>Advanced for PTT hardware options. See also Keyer settings for alternative ways to use the RigPi Keyer board PTT.

Do you know what a 'gimmick winding' (aka 'gimmick capacitor) is? It's been a long time since I have seen or heard the term that describes a twisted pair of insulated wires used to create a very small value of capacitance (~1 pf/inch). They were often found in vintage radio and television sets for use in fine tuning a filter response, interstage coupling, impedance matching, etc. Some service shops and hobbyists would solder in ad hoc gimmick capacitors into circuits to optimize factory sets or maybe to compensate for fixed value components that had drifted in value over time. After achieving the proper value, a dab of wax or cement of some sort is added to keep everything in place. I doubt that gimmick capacitors are acceptable in a high reliability, critical application like spacecraft and military equipment (does anyone know?). Back in my design engineering days I sometime used them in prototypes, along with wire stubs to fine tune amplifier impedance and/or phase matching. Such 'gimmicks' are handy because you can easily tack solder them in place just about anywhere to test the effect of a little extra capacitance, without disturbing the primary circuit components.

Mac's Service Shop: A Little Dog and SSB Tuning Ad

By John T. Frye

Barney was muttering to himself and Mac, his employer, knew from experience that this meant the youth was having trouble with his work. Finally the older man laid down his solder gun and strolled over to where the youth was poking aimlessly around the wiring of a little a.c.-d.c. receiver with the noise probe of the signal tracer.

'Want to tell Daddy?' Mac asked soothingly.

'I want to tell somebody!' Barney exploded. 'This cotton-picking set about has me ready to blow my stack. For a while it plays fine; then it starts getting noisy; next it goes dead on all but local stations; finally it will play OK again for a half hour or so. And it's not tubes, for I've changed 'em all,' he concluded.

Mac cocked a practiced ear at the set that was now in the noisy part of its cycle.

'Bad i.f. transformer?' he hazarded. 'Nope,' Barney denied with conviction. 'I tacked in new ones to make sure.'

'I see it has an r.f. stage. How about the coupling capacitor between it and the mixer?'

'Ain't no such animal. This little gem uses a regular tuned transformer for coupling.'

'Maybe one of the transformer windings is bad?'

Barney shook his head. 'I was just checking both windings with the noise probe of the signal tracer. When you pass a current through a winding from this probe, if there is the least sign of a break in the winding you get a heck of a racket from the tracer speaker.'

'Oscillator coil?' Mac suggested as he picked up the diagram.

'I checked out the two main windings on that, too,' Barney said triumphantly.

'Hm-m-m-m,' Mac said as he studied the diagram. 'This oscillator coil is a little unusual: it actually has three windings. One is the tuned, frequency-determining winding that has its bot-tom connected to the a.v.c. bus. Then there is this feedback winding between the cathode of the 12BE6 mixer and ground. Finally there is this little gimmick winding that has one end going through a 1000-ohm resistor to the oscillator grid. The other end is free. Apparently they just use it for capacity coupling to the tuned circuit. Have you checked for leakage between windings?'

Barney shook his head in a crest-fallen manner and picked up the noise probe. When its leads were connected between the gimmick winding and the tuned circuit winding, a scratching crackling sound came from the signal tracer speaker.

'Guess that's the trouble,' Mac said as he continued to study the diagram. 'When that gimmick winding intermittently short-circuits to the tuned winding, it places the oscillator grid voltage on the a.v.c. bus and biases the tubes so high only the local stations can get through.'

'I'll buy that, but what do we do about it? Os x update for mac. This set's an orphan, and we can't 'get an exact replacement; but on that crowded, shallow chassis, an exact replacement is about the only thing that will fit. I hate to try re-vamping the oscillator circuit.'

'Maybe you won't have to. Try connecting a small mica capacitor, say about a 0.001 μfd., between that gimmick coil terminal and the 1000-ohm resistor. That should furnish a path for the r.f. but block off the oscillator d.c. voltage. Then the gimmick coil can short or not, just as it pleases.'

Barney carried out this suggestion and the receiver acted perfectly normal. Oscillator tracking was not disturbed and there was no sign of noise.

'Why didn't I think of that?' Barney growled. 'This must be one of my stupid days.'

'You would have thought of it,' Mac said soothingly. 'You were on the trail. I just used my experience to beat you to it. I've had quite a bit of trouble with that same general condition with two-winding oscillator coils in which a mica coupling capacitor between the tuned winding and the oscillator grid becomes leaky and produces the same symptoms. But let's talk about something else. How are you making out with that new selectable-sideband ham receiver of yours?'

'Fine, fine,' Barney said; 'and you know something? I'm finding out that quite a few hams who own this general type of receiver do not know how to tune them correctly.'

'Yeah,' Mac said skeptically.

'I know it sounds wacky, but it's true. It's on tuning AM stations they fall down. On SSB, either you tune the thing right or you get nothing but gobbledygook; but you can get some reception of AM stations even though you mistune the set.'

'Spell it out for me,' Mac suggested. 'Well, the main point is that you're supposed to receive just one sideband of an AM station at a time with these receivers. That's all you need since the two sidebands ordinarily carry the same information. Now in order to receive just one sideband, the carrier has to be placed pretty exactly on the selectivity curve of the 50 kc. i.f. passband. You don't place the carrier in the center of that passband the way you do with an ordinary receiver; you put it on the low-frequency skirt.'

'Why?'

'Well, suppose this is the 50 kc. selectivity curve,' Barney said as he sketched a flat-topped hairpin on a piece of paper. 'Now suppose we have the passband adjusted for 3 kc. bandwidth. If we put the carrier in the center, that leaves only 1.5 kc. on either side, which means our high-frequency response will be restricted to 1500 cycles. But if the carrier is put over here about half-way down on the low-frequency skirt of the curve, the sideband can use the full 3 kc. bandwidth, giving us frequency response up to 3000 cycles. There will be some attenuation of the frequencies immediately adjacent to the carrier, but these are very low frequencies that would never be passed by the receiver's audio system anyway.'

'Isn't it pretty hard to know when you have the carrier in just the right place?'

'Not really. There's a simple way of doing it. First, you set the b.f.o. to exactly 50 kc. This is done by tuning in a steady carrier and adjusting the b.f.o. and receiver tuning as you keep flipping back and forth between upper and lower sidebands. When the b.f.o. is set right on the nose, the receiver will stay at zero-beat with the incoming signal as either sideband is selected. From this point on, you do not touch the b.f.o tuning.

'Now you are ready to tune in an AM station the way it should be tuned. To do this, you simply turn on the b.f.o. and zero-beat the carrier of the phone signal. Then you turn the b.f.o. off. The station will be heard clearly and the full bandwidth can be utilized by the desired sideband to provide maximum high-frequency response. If you listen closely, it's easy to see that the 's's' can be heard much more easily in speech when the receiver is tuned in this fashion than is the case when it is tuned in the ordinary way.

'What's more, you can flip from one sideband to the other without there being a bit of difference in reception, providing, of course, there's no QRM on one side or the other.'

'What if there is QRM?'

'That's one of the beauties of setting up the receiver in this manner. If a station comes on near the one to which you are listening and puts a high-frequency heterodyne on the signal, you can usually lose the heterodyne entirely by simply switching to the other sideband. You don't have to touch the tuning when you do this. Neither do you have to retune when varying the selectivity of the receiver. In fact, you can give interference a real battle without ever touching the tuning dial. First you switch sidebands to try to get rid of the interference. In the event that stations are crowding in on both sides of the one you're trying to receive, you can narrow down the bandwidth of the receiver. If a single source of interference still persists, you can finally try to notch it out with the tunable T-notch filter.'

Tuning Radio For Macbook Pro

'Do you always have to use the b.f.o. to place the carrier correctly?'

'You do to place it exactly, but after you get on to it you can come pretty close simply by tuning the receiver to the proper side of the signal being received. With my receiver, and a couple of others that are of the same general design, you tune to the high-frequency side of the signal when using the upper sideband position and to the low-frequency side in the lower sideband position. When I am just tuning around, I never bother to use the b.f.o. to set the carrier; but when I get into a QSO, I usually flip on the b.f.o. for a second or so and zero-beat exactly.'

'Is it always desirable to place the carrier down on the skirt of the passband?'

'Practically always. I've found that when you're copying an extremely weak DX station you can sometimes pull it in just a little better by moving the carrier to the top of the passband. You know the same thing happens in ultra-fringe-area TV reception. Sometimes you have to sacrifice optimum normal-signal tuning - and even alignment-to get a picture at all; but these cases are exceptions to the rule.'

'I'll bet your knowledge of a TV set, which is actually very close to being a single-sideband receiver as far as the picture is concerned, helped you considerably in understanding the working of your new receiver.'

'You can say that again! In fact, I have a heck of a time trying to explain what is going on in our sideband receivers to another ham who hasn't swallowed at least a little TV theory.'

'That's fine,' Mac said as he picked up his solder gun. 'Now let's put some of your excellent grasp of TV theory to practical use. See what you can do with that portable set that has a nasty case of vertical jitter.'

'Do you always have to be so dog-gone practical?' Barney grumbled as he placed the set on the bench.

'Well, Buster,' drawled Mac, 'I don't suppose I really have to be practical, but just as a matter of record it is your jam and cake I'm thinking about as well as my own bread and butter!'

Posted January 14, 2020

Mac's Radio Service Shop Episodes on RF Cafe

Tuner Radio For Mac

This series of instructive stories was the brainchild of none other than John T. Frye, creator of the Carl and Jerry series that ran in Popular Electronics for many years. Mac's Radio Service Shop began life in Radio & Television News magazine (which itself started as simply Radio News), and then changed its name to Mac's Service Shop after the magazine became Electronics World. 'Mac' is electronics repair shop owner Mac McGregor, and Barney is his eager, if not somewhat naive, technician assistant. 'Lessons' are taught in story format with dialogs between Mac and Barney.

Tuning Radio App

• Mac's Service Shop: Not Always Right - March 1956 Radio & Television News
• Television DX - September 1951 Radio & Television News
• Magnetic Shielding - December 1955 Radio & Television News
• Tape Recorder Tips - July 1958 Radio & TV News
• A Typical Day in the Shop - July 1955 Radio & Television News
• Barney Turns Inventor - February 1950 Radio & Television News
• Thoughts on Test Equipment - July 1954 Radio & Television News
• Mac's Radio Service Shop: Portable Patter - April 1950 Radio & Television News
• Mac's Service Shop: Buying and Using a Pocket Calculator - May 1974 Popular Electronics
• Electrostatics at Work - February 1973 Popular Electronics
• Telephone Pickups and Other Subjects - April 1954 Radio & Television News
• Mac's Service Shop: Not Always Right - March 1956 Radio & TV News
• Barney's Dog Show - May 1954 Radio & TV News
• Zenith's 1973 Color Line - March 1973 Popular Electronics
• Always Something New - February 1958 Radio & TV News
• The Time Is Now - March 1958 Radio News Article
• Was Ist Los? - May 1958 Radio & TV News News
• A Little Dog and SSB Tuning - November 1958 Radio & TV News
• New Breed of Test Equipment - September 1972 Popular Electronics
• Barney is Promoted - May 1948 Radio News
• Motorola's 1974 Color TV Receivers - November 1973 Popular Electronics
• New Uses - June 1958 Radio & TV News
• Satisfied Customer Insurance - May 1952 Radio & Television News
• What's Right with the Service Business - May 1955 Radio & Television News
• Summer Seminar - June 1956 Radio & Television News
• Simple Things First - January 1960 Electronics World
• Pride and Prejudice - April 1955 Radio & Television News
• Unusual New Equipment - June 1955 Radio & TV News
• Insurance Jobs - May 1956 Radio & TV News
• Radio Interference - January 1972 Popular Electronics
• How Good Are We? - April 1960 Electronics World
• The Not-So-Simple Sets - October 1963 Electronics World
• Changer Chatter - May 1959 Electronics World
• Servicing Amateur Equipment - July 1959 Electronics World
• How It Started - February 1960 Electronics World
• Two for One - March 1960 Electronics World
• Grasshoppers & Compatibility - December 1959 Electronics World
• Safety in Medical Electronics - July 1969 Electronics World
• Getting the Most from Your Service Dollars - February 1972 Popular Electronics
• Electronics and Psychology - May 1969 Electronics World
• Biological Effects of Electrical Shock - May 1973 Popular Electronics
• Keeping Abreast of Your Field - April 1969 Electronics World
• Servicing Without Service Data - February 1974 Popular Electronics
• Modules and the Technician - January 1973 Popular Electronics
• Salvaging Dunked Radios - July 1972 Popular Electronics
• A Versatile Pocket Calculator - May 1972 Popular Electronics
• Cost of Color TV Service - February 1969 Electronics World
• Leakage Current Testing and Using Square Waves - April 1973 Popular Electronics
• Medical Electronics Servicing - October 1969 Electronics World
• Philosophy of a Kit Manufacturer - November 1972 Popular Electronics
• Fix It or Junk It? - September 1969 Electronics World
• Electronics in Automobiles - September 1973 Popular Electronics
• Being an Amateur Pays Off - August 1973 Popular Electronics
• Electric Shock - August 1969 Electronics World
• A New TV Antenna - December 1972 Popular Electronics
• Single Sideband for the CB'er - June 1970 Popular Electronics
• Meter Accuracy Specifications - April 1972 Popular Electronics
• How to Be a Good Customer - January 1969 Electronics World
• Shelf Life of Capacitors & Batteries - August 1972 Popular Electronics
• Skeeter G's and Test Patterns - June 1951 Radio & Television News
• Designing a Receiver for Cable TV - June 1969 Electronics World
• Electronics and the Energy Crisis - April 1974 Popular Electronics
• Bill Gets the Full Treatment - December 1949 Radio & Television News
• Looking Forward and Backward - March 1951 Radio & Television News
• Taming Transients - July 1963 Electronics World
• Case of the Bad Bypass - December 1963 Electronics World
• Advertising for Dessert - July 1949 Radio & Television News
• A.C.-D.C. Bread and Butter - October 1952 Radio & Television News
• Worth of His Hire - May 1961 Electronics World
• TV and the Little Guy - April 1951 Radio & Television News
• A Breathing Spell - February 1955 Radio & Television News
• Spring Fancies - April 1952 Radio & Television News
• Service Bench Chatter - October 1951 Radio & Television News
• Carbon-Tet Can Kill - February 1952 Radio & Television News
• Something Borrowed - January 1952 Radio & Television News
• Barney, Beauty, and BCI - October 1948 Radio & Television News
• Automation and the Technician - July 1961 Electronics World
• A Windy Subject - March 1953 Radio & Television News
• All Work and No Play - March 1952 Radio & Television News
• Barney, Beauty, and BCI - October 1948 Radio & Television News
• Safety in Servicing - January 1954 Radio & Television News
• Mac and Free Estimates - January 1950 Radio & Television News
• Intermittents Still Pursue - February 1949 Radio & Television News
• Barney Is a Big Boy Now - January 1949 Radio & Television News
• A Little Lightning - July 1948 Radio News
• Mac Quotes Benjamin Franklin - October 1949 Radio & Television News
• Barney Talks A.C.-D.C. - September 1949 Radio & Television News
• Barney Takes on Color - February 1955 Radio & Television News
• Something Borrowed - January 1952 Radio & Television News
• Barney Plays 'Twenty Questions' - November 1948 Radio & Television News