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Repair / Help Forum => Repair / Help => Topic started by: scorpio333 on December 19, 2019, 05:11:26 PM

Title: Replacing fuse type bulbs with LEDs
Post by: scorpio333 on December 19, 2019, 05:11:26 PM
Looking for opinions from those who have done it or those who have seen a receiver with the LED bulbs. My Superscope QRT440 (Marantz) has one bulb out and it drives my OCD crazy. Unlike the Marantz blue, Superscope used pinkish purple for the display. My concern is LEDs can be overly bright and I'm worried if the replacements are too bright that the display is going to be too pink or Hello Kitty-ish - some may say it's already too pink. That's fine, the sound it produces more than makes up for the color and how can you not like the built in 8 track???  >:D

Here's a pic (not mine)
(https://i.ebayimg.com/images/g/QpwAAOSwo0JWL0CC/s-l1600.jpg)
Title: Re: Replacing fuse type bulbs with LEDs
Post by: rgpit on December 19, 2019, 06:20:45 PM
You can adjust the LED's brightness with the appropriate series resister.

https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-led-series-resistor (https://www.digikey.com/en/resources/conversion-calculators/conversion-calculator-led-series-resistor)
Title: Re: Replacing fuse type bulbs with LEDs
Post by: Sir Thrift-a-Lot on December 19, 2019, 07:59:55 PM
I don't think brightness is the only issue, color temperature is just as much if not more of an issue.   I would either do everything LED or find a single fuse bulb to match what you have.   I'm eventually going to LED my Marantz, I can give you a bulb or two from it if you want.
Title: Re: Replacing fuse type bulbs with LEDs
Post by: MacGeek on December 19, 2019, 08:28:24 PM
I don't think the color matters because that is a cool looking unit, and quad to boot.
Title: Re: Replacing fuse type bulbs with LEDs
Post by: scorpio333 on December 20, 2019, 10:07:50 AM
I don't think the color matters because that is a cool looking unit, and quad to boot.

I'm not familar with quad, while googling around I found a forum post that mentions this amp is a very primitive quad. Being from '73 it was likely a first attempt at quad.

I don't think brightness is the only issue, color temperature is just as much if not more of an issue.   I would either do everything LED or find a single fuse bulb to match what you have.   I'm eventually going to LED my Marantz, I can give you a bulb or two from it if you want.

I may take you up on that, if the LEDs don't work out. The plan was to LED all five bulbs. The bulbs are only $5 from PE so I'll give it a go. If they are too bright I can go the resistor route rgpit mentioned. Or add a diffuser, dull the bulbs, etc.
Title: Re: Replacing fuse type bulbs with LEDs
Post by: Dicky on December 20, 2019, 12:51:58 PM
Contact this guy, and tell him what you want and how you want it to look.  He'll have you covered both ways more than likely (incandescent and LED).

https://sites.google.com/site/dgwojocom/
Title: Re: Replacing fuse type bulbs with LEDs
Post by: scorpio333 on December 20, 2019, 08:05:42 PM
Thanks Dicky, I
Title: Re: Replacing fuse type bulbs with LEDs
Post by: quaddriver on June 26, 2020, 11:59:29 AM
old topic but for future ref:  parts express makes the LED bulbs in warm white now (same price and cool white or cool blue) and the color temp does not alter the display, but it makes it sharper.  leds give off a crap ton of UV regardless of shading and that can act with certain colors and change the hue.

appx $5/5 plus shipping.  I did the same change on my R340
Title: Re: Replacing fuse type bulbs with LEDs
Post by: scorpio333 on June 27, 2020, 10:32:53 AM
Thanks. The receiver is on the shelf at the moment until I can find time to diagnose a bad channel issue.