I have inherited a fairly old Sharp amplifier which does not power on anymore. After poking around with a multimeter we notice that power stops flowing at a DEC Type DG1U TV-5 relay which is rated 8(2)/60A / 18VDC. My plan is now to replace this, however, there only seem to be relays of this type with 8/60A / 12VDC for purchase online.

Would 12VDC be a suitable replacement? We don't plan on driving a huge sound system (nor very loud) with this - at most a couple smallish tower speakers "rated for max. 90W" (what the sticker says).

I should also maybe note that I'm in Austria where we have 230V.


The 18VDC refers to the coil drive voltage. If you just replace an 18 volt relay with a 12 volt relay, the coil will get 50% more voltage than it is rated for, and may (will) overheat. However, you can easily fix this. The 12VDC models have a coil resistance of 275 ohms. If you wire a 137 ohm resistor (1/2 watt power rating) in series with the coil, the resistor will drop 6 volts and the coil will be driven correctly. Since finding a 137 ohm resistor may be difficult, a 120 or 150 ohm resistor will suffice.

  • \$\begingroup\$ A pot could be used or a 137 could be found in a bag of wide tolerance resistors maybe \$\endgroup\$ – JFA Apr 27 '14 at 2:35

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