High Voltage Condensers for Antique Radios
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.
High Voltage Condensers for Sale
* All High Voltage Condensers are new stock. * Condensers have high
working voltages for
dependable radio operation and long life. * All high voltage condensers have long leads, ideal
for hand wired circuits.
* The Electrolytic Condensers we sell are compact and can be installed under your chassis,
letting you leave the old condensers on top of your chassis for original appearance.
* 250 volt, 350 volt , 450 volt, 500 volt and 600 volt electrolytic
condensers for AC radios and 160 Volt condensers for AC/DC tube radios.
* We carry a complete range of Film Capacitors for tube radios, including:
Metallized Polyester Film Condensers * Metal-Foil Polypropylene Condensers and * 400V and 630V Mylar Film Condensers "on sale by the 100". * If you need more than 630 volts we have 1600V Film and Ceramic disc condensers rated at 1600 volts. Our line of Film Condensers offer *
high capacitance stability and reliability; * operate over a wide temperature range * have tight tolerances. * have good solder-ability * and have a flame resistant epoxy coating. * Condenser Tips.
How to Order Condensers
To order by mail:
Condenser Order Form.
Mail it with payment (MO, PO or check) payable to
Dave Cantelon, 6 Ferncrest Gate, Scarborough, Ontario, Canada, M1W_1C2.
To order "online": Email us at:
and tell us
quantity of condensers you need by
uF value, voltage and type. Based on $ price list
, you can then pay
"online" with credit card via PayPal.
Please note that all prices are quoted in US $'s. Minimum order is $20.00 US. For USA
and Canada, fixed shipping charge $7.90 for "airmail". Other countries pay actual
shipping costs. All sales include Money Back Guarantee. Please see
Terms of Sale
RESISTORS for Tube Radios
Resistor $ Price List
About JustRadios ...
$ Price List, Order Form and Terms of Sale
Condensers for Tube Radios and Amplifiers:
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 ) :
Tube Radio CONDENSER Basics
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.
- Don't let terminology confuse you….."condenser" is just an old fashioned name for "capacitor". If you're not the best speller, a condenser, capacitar, capaciter, capacitor, condensar and condensor are also the same.
- Condensers have a capacitance value and a voltage rating. The capacitance value is a measure of how much electric charge a condenser can store. The voltage rating is the maximum voltage the condenser can handle without breaking down.
- Your old tube radio uses 4 types of condensers: variable (tuning) condensers, mica condensers, paper condensers and electrolytic (filter) condensers. When you restore an old radio you will replace the paper and electrolytic condensers, but not the variable and mica condensers.
- In radio service literature such as Sams Photofacts, paper and electrolytic condensers are usually expressed in terms "microfarads". Short forms for microfarad include mfd, MFD, MF, UF and uF. The mica condensers in your tube radio will have lower capacitance values than the paper and electrolytic condensers. Micas are expressed in terms of micromicrofarads (picofarads). Short forms for micromicrofarads include mmfd, MMFD, MMF, PF and pF. A pF is one-millionth of a uF. For example, a mica condenser valued at 500 mmfd (pF) would be 0.0005 mfd (uF).
- As a general rule, if a condenser in your radio is less than 0.001 uF, it is probably a mica condenser. If it is between 0.001 uF and 1.0 uF it is likely a paper condenser and if it's more than 1 uF it's probably an electrolytic condenser.
- Size wise, the electrolytics are the largest condensers and most tube radios use 2 or 3 of them. The original electrolytic condensers are typically the size of a roll of quarters or larger. On the old AC sets they are usually encased in aluminum and mounted on top of the chassis. With the lightweight AC/DC sets of the 1950's they are quite often under the chassis and may have a cardboard case.
- The original paper condensers in your radio will likely be in a brown paper tubular case (sometimes coated with wax). They are usually 1 to 1 1/2 inches long and 1/4 to 1/2 inches in diameter.
- Mica condensers come in different sizes and shapes, but the most common shape is square or rectangular….brown in color with colored dots (sort of look like "dominos").
- Condensers have either "radial" leads or "axial" leads. With "radial" type, both leads exit from the same end of the condenser. With "axial" type, there is a lead at each end of the condenser. Both types are equally good. Just be sure the condensers you order have long leads.
- On schematic diagrams the flat side of the condenser symbol is the positive (+) side and the curved side is the negative (-) side. The positive end must be kept at the higher electrical potential (more positive voltage). Modern film condensers are non-polar, so you don't have to worry about polarity when replacing old paper caps with new film condensers.
- How about using NOS (New "Old Stock") Condensers? These are not recommended…use at own risk! As paper and electrolytic condensers age their capacitance values drift, they dry out and they become leaky. Would you drive a 1930's automobile with NOS 70-year-old tires?
- Don't waste your money on audiophile, computer grade or tantalum condensers. Sure they are good condensers, but your old tube radio does not have the electronic circuitry to take advantage of those expensive condensers. The only difference you will notice is a lighter wallet.
- Plastic / polyester film condensers are now used in place of paper condensers due to their smaller size, lower cost and superior performance. There are many variations of plastic / polyester condensers. What is a Mylar? Mylar is simply the trade name of the synthetic film registered by E.I. duPont de Nemours and Co. Inc.
- What should it cost you to replace the condensers in your radio? To "recap" a typical 5-tube radio you will need a couple of electrolytic condensers and about a dozen film condensers…..Total cost for these parts should be $10 or less.
Non-Electrolytic CONDENSER Tips
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 CONDENSER Tips
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 email@example.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
Condensadores y Diagramas Esquemáticos para las Radios del Tubo de la Vendimia
Dave and Babylyn Cantelon, 6 Ferncrest Gate, Scarborough, Ontario, Canada, M1W 1C2
This page was last updated 2010.