For Sale: High Voltage Condensers for antique tube radio restorations. All electrolytic condensers and film condensers have high working voltages and long leads making them ideal condensers for tube radio repairs. Our Condenser Product Line has been specifically chosen for antique tube radio repairs and restorations. Condenser Tips.

Metalized Polypropylene Capacitors - 630V & 1000V Axial Tubulars
Metallized Polyester Film Capacitors - 630V & 1000V Axial Tubulars
Metallized Polyester Film Capacitors - 6000V Axial Tubulars
Metal-Foil Polypropylene Capacitors- 630V Orange Dips
Metallized Polyester Film Capacitors - 630V Orange Dips
Metallized Polypropylene Capacitors- 1600V Orange Dips
Mylar Film Capacitor "Bargain Bin" - on sale in Bags of 50
High Voltage Electrolytic Capacitors - Radial Leads
High Voltage Electrolytic Capacitors - Axial Leads
Ceramic Disc Capacitors - 1600V
Silver MICA Capacitors- 500V and 1000V

X1/Y2 Disc Safety Capacitors - 250VAC
Y2 Film Safety / Interference Suppression Capacitors - 250VAC
X2 Film Safety / Interference Suppression Capacitors - 275VAC

hot Condenser KITS - for vintage tube radio & amp restorations

Condenser Tips ( for the beginner ) :

• Your vintage tube radio needs both direct current (DC) and alternating currents (AC) to operate. Condensers act to pass AC while blocking DC. Condensers are used to block, pass, filter and tune the various currents in your radio.

• When replacing old paper/wax condensers, you can't go wrong using film condensers that have a higher voltage rating than the paper ones you are replacing. For example, if you are replacing a paper condenser rated at 400 volts, you can use a 630-volt film condenser (but not a 200-volt condenser). A film condenser with a higher voltage rating will give your tube radio better reliability and longer life.
• Why were tube radios manufactured with 200, 400 and 600 volt paper condensers if 600 volt could have been used for all the condensers. Two reasons… cost and size. Condensers used to be expensive so if a manufacture could use lower voltage condensers in a circuit, it could cut production costs. Also, the higher the voltage the larger the paper condenser, so it was easier to install lower voltage paper condensers. Now-a days, film condensers are inexpensive and compact, so use 630 volt film condensers and you can't go wrong.
• Schematic Diagrams and parts lists sometimes do not specify the working voltages of non-electrolytic condensers. To be safe use a film condenser rated at 630 volts.
• Old paper/wax condensers are one of the most unreliable parts in an old radio. Don't let "molded" paper condensers fool you. They are just paper condensers in plastic cases and are just as unreliable as the ones coated in wax.
• Modern non-electrolytic condensers i.e. mica condensers, film condensers, ceramic condensers, etc are non-polar. This means you don't have to worry about which end to connect when replacing old paper condensers with new film condensers.
• When replacing paper condensers with film condensers keep in mind that capacitance values are "easy to please". The uF value does not need to be exactly the same. For example; if replacing a 0.05 uF you can use a 0.047 uF; if replacing a 0.002 uF you can use 0.0022 uF. These replacements are virtually identical. If you are +/- 10% you be well within your radios factory specifications. (Just be sure your replacement condenser has a working voltage is equal or greater than the original paper condenser)

• Electrolytic condensers are often referred to a "filter condensers". Electrolytic condensers help to convert (filter) AC (alternating current) power into the DC (direct current) voltage that your radio tubes need to operate.
• Size wise, the electrolytics are the largest condensers. On older sets they are usually encased in aluminum (can type) and mounted on top of the chassis. If they are not on top of the chassis you will find them under the chassis.
• Condensers used to be much larger and much more expensive than they are today. To save on space and cost "multiple section" electrolytics were used. These are simply two, three or four condensers in the same case. You will notice just one ground connection (black wire) as all the caps share that ground. These "multi-section" caps can be replaced with single electrolytics. Modern electrolytics are compact and will easily fit under the chassis. You should leave the old can condenser on the chassis for original appearance. Just be sure to disconnect it.
• Electrolytic condensers work hard and are probably the most unreliable part of an old tube radio. As they wear out (or simply get old) you get that famous "tube radio hum". Yes, in most cases it is bad filter condensers that are the cause of that hum. WARNING! If you radio hums "turn it off and don't use it". Bad electrolytics are not only hard on your ears; they are hard on the tubes, transformers and other parts in your radio. Condensers are cheap….tubes and other parts can be expensive and hard to find.
• Electrolytic condensers have a rated "working voltage" (WV) which is the voltage it can handle. Ideally, an electrolytic condenser should be operated at a voltage between 1/3 and 3/4 of its maximum working voltage. This is enough voltage to keep the electrolyte from drying out while it allows some margin of safety for unexpected voltage surges. Never replace an electrolytic with one that has a lower voltage rating.
• As with paper condensers, the capacitance value of electrolytic condensers is "easy to please", and an exact uF replacement is not necessary. For example, you can replace a 30 uF with a 33 uF or replace a 20 uF with a 22uF. If you can't find a close replacement …better to go with a higher uF value than a lower uF.
• Warning ! Electrolytics have a negative end and a positive end…..if you install an electrolytic with the polarity mixed up not only will your radio not work…the electrolytic condenser could explode.
• As a general rule AC (tube radios with power transformers) can use 450 volt electrolytics while lightweight ac/dc tube radios can use 160 volt filter condensers. However, there are exceptions so always best to refer to a schematic.
• Electrolytic condensers have a shelf life of a couple of years, so make sure you are buying "fresh" stock electrolytics (not new "old stock"). Would you buy stale loaf of bread if a fresh one available?
• Electrolytic condensers should be stored at temperatures of 5 to 35 degrees C (40 to 95 degrees F) and in non-humid conditions (less than 75 relative humidity) to maximize shelf-life.
• Don't put your tube radio into storage after you have restored the electric's. Once a month let the radio sing for a half-hour or so. This will prevent the electrolytic condensers from drying out.

CONDENSER Installation Tips

• When restoring an old tube radio it standard practice to replace certain of the radios condensers. This is known as "recapping" a radio. An old radio may work with it's original caps….but for how long ?? ….and how safely ?? If the radio is going to be sold with a guarantee or is being given to someone as a gift, you should "recap" the radio.
• You will want to replace all the paper and electrolytic condensers. However, "do not replace the mica condensers". Mica condensers very rarely go bad and if you replace them it will throw off the radios tuning. Replacing the mica condensers will do more harm than good. Only replace a mica if you are sure it is bad (which is rare).
• Get a schematic (and parts list) before you start your recap job. It is often impossible to read the values that are on the original condensers. Also, if the radio was repaired at some time in the past, there is a good chance someone threw in the wrong size cap, just to get the radio working. Without a schematic you'll be guessing.
• Before replacing the condensers, check the radios' resistors. Since you will be replacing the caps anyway, you should snip one lead of each paper and electrolytic condenser. This will help prevent false resistance readings.
• Put "heat shrink" tubing on the leads of the condensers and resistors before you solder them into the circuit. This will help prevent dangerous shorts.
• Always check a condenser before installing it. Although it is very rare, every once in a blue moon, a new condenser will be defective or off spec. Taking ten seconds to check a condenser can save you hours of troubleshooting…..only to find out you accidentally installed a brand new "bad" condenser.
• If you need a higher uF than is available from your retailer, you can connect a couple of condensers in parallel (side-by-side). For example if you need 200 uF at 450 volts you could connect two 100 uF / 450 volt condensers in parallel and you would end up with 200 uF at 450 volts. You have kept the voltage the same while doubling the uF.
• If you need a higher working voltage, you can connect a couple of condensers in series (end-to-end). For example two 100 uF at 450 volts in series would give you 50 uF at 900 volts. You have doubled the voltage and halved the uF.
• Last but not least…where can one buy the right sizes and right types of condensers needed to restore a tube radio? You have found the right place….we are Dave and Babylyn Cantelon. We specialize in Condensers for vintage tube radios. Got a tube radio condenser question….email us at justradios@yahoo.com. Like to place a condenser order…here is our Condenser Order Form. .

Nous nous spécialisons dans les schémas par radio antiques / diagrammes schématiques et les condensateurs de film et électrolytiques à haute tension pour des radios de tube. Wir spezialisieren uns auf antike Radiodiagramme / schematische Diagramme und Hochspannungsfilm- und elektrolytischekondensatoren für Gefäßradios. Ci specializziamo negli schemi radiofonici antichi / schemi schematici e condensatori elettrolitici ad alta tensione e del pellicola per le radio del tubo. Nós especializamo-nos em diagramas esquemáticos de rádio antique / diagramas esquemáticos e capacitores de alta tensão do película e os eletrolíticos para rádios do tubo. Nos especializamos en diagramas esquemáticos de radio antiguos/los diagramas esquemáticos y los condensadores de alto voltaje del película y electrolíticos para las radios del tubo.

Antique Radio Schematics - JustRadios

Dave and Babylyn Cantelon, 6 Ferncrest Gate, Scarborough, Ontario, Canada, M1W 1C2

E-mail: justradios@yahoo.com

This page was last updated 2023.