mfforever Posted April 5, 2023 Posted April 5, 2023 My only resistor in a 58 year old crossover ( do they stay alive / true to specs for nearly 60 years ? ) Based on my net readings, the answer is 5 Ohms (. Sounds like school so long ago ......... " Find X in this equation " . Please see detail below. Quote 1
muon* Posted April 5, 2023 Posted April 5, 2023 (edited) ............. I tried, but the colour codes still confuse me, especially when there are charts for three band and charts for 5 bands and so on, and flip the resistor over and it reads a different way. Someone else will look after you. Edited April 5, 2023 by muon* 1
BugPowderDust Posted April 5, 2023 Posted April 5, 2023 This should nut it out if you have one in front of you. 1
Monkeyboi Posted April 5, 2023 Posted April 5, 2023 0.5 ohms at +/- 20% tolerance. So anything between 0.4 and 0.6 ohms is acceptable. Resistors rarely go lower in resistance, but can go high or even open circuit. Been 58 years old it's probably either a wirewound or a carbon composition resistor. The latter can deteriorate over time as moisture can eventually make its way into the compressed carbon inside the resistor body. Check with your multimeter. 2
mwhouston Posted April 5, 2023 Posted April 5, 2023 1 hour ago, mfforever said: My only resistor in a 58 year old crossover ( do they stay alive / true to specs for nearly 60 years ? ) Based on my net readings, the answer is 5 Ohms (. Sounds like school so long ago ......... " Find X in this equation " . Please see detail below. Meter. 1
mfforever Posted April 5, 2023 Author Posted April 5, 2023 (edited) Thank you all above ..... and yes, Monkeyboi, rechecking it is .5 Ohms with a plus/minus 20%. Alas, I was being lazy as I did not want to cut one wire lead to the resistor to get an accurate reading on my multimeter but I will have to do so just to be sure it is within tolerance.. I can't say I enjoy soldering as it makes me anxious ( burning out my components and / or burning my hands ) but without doubt the more I do the better I get. If it is within tolerance I will leave it ........... if not, will buy some ....... METAL OXIDE ones are best ??????? Edited April 6, 2023 by mfforever 1
Monkeyboi Posted April 6, 2023 Posted April 6, 2023 11 hours ago, mfforever said: Thank you all above ..... and yes, Monkeyboi, rechecking it is .5 Ohms with a plus/minus 20%. Alas, I was being lazy as I did not want to cut one wire lead to the resistor to get an accurate reading on my multimeter but I will have to do so just to be sure it is within tolerance.. I can't say I enjoy soldering as it makes me anxious ( burning out my components and / or burning my hands ) but without doubt the more I do the better I get. If it is within tolerance I will leave it ........... if not, will buy some ....... METAL OXIDE ones are best ??????? Up to 3 watts there a plenty of resistor types to choose from. Metal oxide is very stable but wirewound are too. If you ever feel the need to replace it then 0.47 ohms is the closest easier to obtain preferred value and with +/- 5% tolerance the newer resistors will well within the specification. If however, as you have determined, it's close to the 0.5 ohms I would not replace it from a fault rectification POV. IOW, if it ain't broken you don't need to "fix" it.
mfforever Posted April 6, 2023 Author Posted April 6, 2023 Thanks Monkeyboi .............good advice all round ...... hopefully will measure well .... will see in a few days......... 1
mfforever Posted April 12, 2023 Author Posted April 12, 2023 WOW ........ the first one reads 19.3 Ohms so it's long gone ....... Can get some. .5 Ohms. wire wound 3 Watt VISHAY ones from au.element14.com. ( luckily in stock ). ...... will get 2....
mfforever Posted April 12, 2023 Author Posted April 12, 2023 (edited) OK ......... I stuffed up and was lucky that I had not installed them ( and sorry for wasting some of your time ) Whilst looking at some Magnum K Crossovers on the net, I noticed that they had a BROWN Band first, thus making it a 4 BAND resistor ( and not a 3 band as I thought ) ....... I looked at mine again and yes, there was the faintest brown band against the brown body .....I had not noticed it before. So it goes. Brown....Green ...... Black ........ Silver..... giving a value of 15 Ohms, plus/minus 10 %. Will need to replace them as my 19.3 Ohms multimeter reading is too high for the specified 15 Ohms Looking at Mundorf MOX 15 Ohms. 5 Watts ...... Edited April 12, 2023 by mfforever 2
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