![]() Though FM Discriminators can have higher voltage than AM detectors. Main difference are maximum current and voltage, which is usually not important on Radio Detectors or Mute circuits. ![]() The "real" 1N60 and 1N34A (see link) are nearly twice size and similar to each other.Īny of these will probably do for Germanium. The 1N914 & 1N4148 are small glass package. It's Silicon like 1N4148 and much the same. Gives a lot of 1N34A, which in most cases are also OK replacement, but the 1N60 is maybe better voltage rating and speed (shortwave).ġN914 is listed by some as Germanium, which is nonsense. Power rectifiers (Metal or Selenium) best only replaced by 1N4007 with series resistor. Earlier on domestic radio is usually something else that can be replace with Germanium for signal. ![]() It's unlikely any domestic radio earlier than 1965 is silicon signal diode, 1946 to 1960s is Germanium. China, Thailand, Turkey and other countries selling them. About $5 to $10 for 100, possibly including postage. With some care you can make Copper Oxide diodes and rectifiers at home.Ĭhinese eBay sellers describe them as Schottky, some sell Silicon diodes described as like 1N60īuy ones described as Germanium. Before Germanium (1938? domestic from 1946) and Silicon (1940s?) diodes Copper Oxide was the most common signal diode, even used in 1930s ring diode mixers for cable telephony SSB. Also a diode in a Triode or Pentode envelope was cheaper than semiconductor diode. Valve (Tube) signal diodes used till 1960s as cheap. But from late 1920s valves (tubes) better and cheaper. Semiconductor diodes have existed since 19th C. The 1946 1N60 is quite different package style to "modern" 1N60 which also likely isn't made the same way. * Replacing vintage UHF/Microwave detector or mixer diodes needs more thought and specialist devices. The 1N4007 works as PIN above 1MHz as it's so slow due to high PIV rating that it won't rectiify RF, thus several volts of RF can be variably attenuated by 0.01mA to 10mA forward current. Oddly an 1N4007 but not so well an 1N4006 or less can be used as a cheap and poor Varicap or PIN (variable RF attenuator by forward Current). Schottky power rectifiers only up to about about 25V. High voltage SMPSU/Inverters need UFnnnn or MURnnn series equivalents. Mains Transformer LT, HT or Vibrator packs. Add a series resistor to simulate resistance of original metal Rectifier. But I can't think of any vintage signal application where 1N60 (Ge) or 1N4149 (Si) doesn't do.įor 20Hz to 400Hz power 1N4007 LT or HT up to 1000V and 1A. Sometimes (rarely) a Shottky diode such as HP 5082-2800 could be used. Most situations except a bias diode will work with these. If Silicon will do (0.6 to 0.7V) then 1N4148. But I can't think of any vintage applications using other than tube/valve rectifiers except waveguide based microwave detectors*. Above 20MHz to 35MHz the Schottky such as HP 5082-2800 may be best. They are more sensitive than best Schottky or regular Silicon up to about 30MHz anyway. If it really needs Germanium (low signals, high sensitivity) I use modern 1N60 (0.15V drop). Only TV flywheel sync likely to exceed 1N4148 To thank the Author because you find the post helpful or well done.įor signal diodes the PIV is main thing. There are other diodes in this unit, so if I do find a source for 1N295 replacements, I will buy enough to replace all six unless they turn out to be costly.Īll help will be very much apreciated, as I am overwelmed by this. They are M5 and M6 in the Sam's photofact (date 12-58, Set 425, folder 7) link: ( fisher_90t_part2), which is listed in circuit on this schematic page of the photofact: ( usa_fisher_90t_sch1c). I will give my specific problem for you to digest: I have a Fisher 90-T which needs a set of diodes on the muting circuit. I have learned that diodes are used for more than one function, and selecting a diode depends on the intended use. The toughest thing for me is that the many manufacturers list different electrical specifications, so matching them based on specs is next to impossible for the novice. Furthermore, the cross references are old, and even those list obsolete part numbers. Diodes go bad and finding an exact part number replacement is hard to impossible. Days of asking and searching left me with more questions that answers. This is a tough nut to crack, and when I left the question on the diyaudio tube forum, I did not get the answers I needed.
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