Free Technical Repair Tip: reading the value of small (disk) capacitors. Older USA style capacitors were labeled directly in picofarads or microfarads. Sizes under 1000pF were labeled 10 for 10pF or 470 for 470pF etc. Sizes starting with a decimal were labeled directly in microfarads so a .001 means .001µF! A capacitor labeled .047 would be .047µF or .1 would be .1µF!
Modern small value capacitors between 100pF and .1µF are labeled using the "first two digits" plus a "multiplier" ! A capacitor labeled 101J or 101K or 101M would be 1-0 plus the "multiplier" adding "1-zero" =100pF. A capacitor labeled 103 would be 1-0 plus the "multiplier" adding "3-zeros" =10,000pF (same as .01µF). A capacitor labeled 473 would be 4-7 + 3 zeros to follow = 47,000pF (= .047µF). A capacitor labeled 104 = 100,000pF (= .1µF)! Commonly seen letters: J =5% tolerance; K =10% tolerance; M =20% tolerance; F =1% tolerance; G =2% tolerance.

Free Technical Repair Tip: random noise or static: Tube units made before 1970 contain paper bypass & coupling capacitors which can be identified by a wax coating. When these get old they cause noises which may be hard to identify by freeze spray. Professional restorers of antique & vintage tube radio equipment make it a practice to replace all old paper capacitors to eliminate shorts, static, and imminent additional repairs.

Free Technical Repair Tip: Vibrator going bad in vintage mobile tube-type radios: The Wax-coated paper BUFFER capacitor (under the vibrator socket) is there to reduce arcing across the vibrator contact points; when it goes bad--the Vibrator "spot welds" itself together! The replacement BUFFER capacitor should be 1000V or higher with a capacitance range of -25% to +50% of the original value. most vibrator buffer capacitors are between .003 and .015µF at 1200 to 1600 Volt.

Free Technical Repair Tip: Recent (1990 & newer) CHINA-BUILT STUFF (Computers, Televisions, Computer & Video Monitors, Boomboxes & Stereos, CD & DVD Players, VCR's etc.) use Switch-Mode Power Supplies to reduce the cost, weight, & size of STUFF.
Switch-Mode Power Supplies use inadequately rated High Temperature 105°C capacitors (usually 47µF to 4700µF) to make them very FAILURE-PRONE! Look at these capacitors carefully: some have bulging (split/cracked) metal tops! The bulge shows that they are FRIED-BAD (leaky or shorted)!
You should replace all similar capacitors in that area (including capacitors that aren't yet bulging) as they will FAIL SOON! Capacitors that hiss, snap, crackle, or pop (when the unit is on) are getting ready to explode! Use the next higher voltage to replace these High Temperature capacitors.
We now live in the "throw-away society" where "Alphabet Soup Appliance" "Big Mart" and "Shifty Takers" stores demand manufacturers supply products that will die as the warranty expires! They intentionally use inadequately rated parts because consumers waste THOUSANDS of DOLLARS every year throwing stuff away instead of spending $5 to $25 for parts to fix STUFF and make it more reliable!

Free Technical Repair Tip: Hum Tube type Antique, Vintage, and CB Radios & Linear Amplifiers have a "high voltage B+" power supply consisting of a power transformer, rectifier, & filter capacitors; this converts the power from your outlets 117AC line voltage to appropriate DC voltages which power various circuits of the radio. Heat, old age, and chemical leakage make electrolytic capacitors deteriorate; the result is a loud "buzz" or humming sound. Some bad capacitors may show white-ish deposits indicating that they have been leaking or may be bulging! Can-style (multi-section) capacitors are no longer made (Kens Electronics has a few "NOS" in stock); smaller modern electrolytic capacitors can be installed under the chassis (on terminal strips) with the can left in place (disconnected electrically) to maintain the classic-vintage appearance. Caution: beware--tube units have exposed wires & terminals that may be charged with hundreds of volts. Severe Shock & burns will occur if you touch these without discharging--grounding these parts (using a resistor) first. Seek the assistance of a professional electronic technician if you are unsure how to proceed!

302 & 308M	240009	240008	462 & 469

D&A-2111	D&A-2112	D&A-HF35	D&A-MC35S