Dave, How many of those pots do you need? I've had the innards of an 88(something) lying around for ages and your welcome to a few, if you're willing to pay shipping from the Netherlands. With only the trimmers in a small box, that should not break the bank. Met vriendelijke groet, Rob Klein. Verstuurd vanaf mijn tablet Dave M <dgminala@mediacombb.net>schreef: >I tried to find this style trimmer pot with a wirewound resistance element, >but found that all I could find was the Cermet type. It appears that >wirewound pots have all been replaced by Cermet. the wirewound pots had a 1W >power rating, whereas the Cermet pots arte only rated at 3/4W. In the 720A, >the reduced power rating won't be an issue, but in some vintage equipment, >it might be. > >I've also tried, to no avail, to find a source for the metal-cased wirewound >trimmer pots used on the K-V divider in some older Fluke differential >voltmeters, such as the models 883A, 885A and 887A. Does anyone know of a >source for replacements for those pots? I have an 887A on the shelf that >I'd like to get back to original condition if I could find a couple of that >style trimmer pot. They're only 2 ohms, making the search even more >difficult. At this point, my only recourse is to find a defunct donor unit >at reasonable cost, and salvage the parts. Does anyone have a hangar queen >that I could get for shipping charges? I'd be really happy to get mine back >on the road to health. > >Cheers, >Dave M > >Tony wrote: >> Apologies - my mistake - I wasn't paying sufficient attention when >> Google decided that this was a perfect match when searching for >> 300SP-1-502: >> http://uk.farnell.com/webapp/wcs/stores/servlet/Search?st=3400s&catalogId=15001&categoryId=700000005471&langId=44&storeId=10151 >> >> But £180.27 each whereas Newark, the US arm of Farnell only want $120 >> or approx £80 for the same part! Are there really that many Brits who >> put up with being ripped-off to these levels? >> >> Tony H >> >> >> On 26/09/2015 01:27, Charles Steinmetz wrote: >>> Charles wrote: >>> >>>>> I had to look it up. The company was Arrow (800 833 3557). The pots >>>>> were manufactured by Bournes with a manufacturer part number of >>>>> 300SP-1-502. Unit cost $7.73 in 2011. I bought 26 so my cost was >>>>> about $200. I wanted a "Manufactured in America" part but can't >>>>> remember if that was too pricey or not. >>> >>> Tony wrote: >>> >>>> They are now $92.55 from Arrow now and Farnell want over $200 each >>>> if you buy 25 or more!!!! There don't seem to be any obvious cheap >>>> alternatives for 10 turn 20ppm/C 5W pots. >>> >>> The original pots were Bunker Ramo-Eltra (later, Bunker >>> Ramo-Amphenol) P/N 3800P-502. These were 20-turn, 5k, 10%, 1W, >>> +/-50 ppm/C wirewound parts in the 34b rectangular package. The >>> Bourns 3005P-1-502 matches these specifications (I suspect "300SP" >>> in Charles's message was a typo). I do not know if the pin layout >>> is the same as the 3800P-502. Verical has the lowest price on the >>> 3005P-1-502 that I could find in a quick search, $7.68 each. Others >>> charge from $9 to $14. Tony -- what part number were you quoting specs >>> and prices for? I >>> found nothing searching for "300SP-1-502." >>> >>> Best regards, >>> >>> Charles > > >_______________________________________________ >volt-nuts mailing list -- volt-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >and follow the instructions there.

Rob Thanks for the offer. I received an offer of a (nearly) complete unit from another list member. If that turns out well, I should have all the spares that I'll ever need. If it doesn't work out, I'll surely be back in touch with you. Dave M Rob Klein wrote: > Dave, > > How many of those pots do you need? I've had the innards of an > 88(something) lying around for ages and your welcome to a few, if > you're willing to pay shipping from the Netherlands. With only the > trimmers in a small box, that should not break the bank. > > > Met vriendelijke groet, > Rob Klein. > > Verstuurd vanaf mijn tablet > > Dave M <dgminala@mediacombb.net>schreef: > >> I tried to find this style trimmer pot with a wirewound resistance >> element, but found that all I could find was the Cermet type. It >> appears that wirewound pots have all been replaced by Cermet. the >> wirewound pots had a 1W power rating, whereas the Cermet pots arte >> only rated at 3/4W. In the 720A, the reduced power rating won't be >> an issue, but in some vintage equipment, it might be. >> >> I've also tried, to no avail, to find a source for the metal-cased >> wirewound trimmer pots used on the K-V divider in some older Fluke >> differential voltmeters, such as the models 883A, 885A and 887A. >> Does anyone know of a source for replacements for those pots? I >> have an 887A on the shelf that I'd like to get back to original >> condition if I could find a couple of that style trimmer pot. >> They're only 2 ohms, making the search even more difficult. At this >> point, my only recourse is to find a defunct donor unit at >> reasonable cost, and salvage the parts. Does anyone have a hangar >> queen that I could get for shipping charges? I'd be really happy to >> get mine back on the road to health. >> >> Cheers, >> Dave M >> >> Tony wrote: >>> Apologies - my mistake - I wasn't paying sufficient attention when >>> Google decided that this was a perfect match when searching for >>> 300SP-1-502: >>> http://uk.farnell.com/webapp/wcs/stores/servlet/Search?st=3400s&catalogId=15001&categoryId=700000005471&langId=44&storeId=10151 >>> >>> But £180.27 each whereas Newark, the US arm of Farnell only want >>> $120 or approx £80 for the same part! Are there really that many >>> Brits who put up with being ripped-off to these levels? >>> >>> Tony H >>> >>> >>> On 26/09/2015 01:27, Charles Steinmetz wrote: >>>> Charles wrote: >>>> >>>>>> I had to look it up. The company was Arrow (800 833 3557). The >>>>>> pots were manufactured by Bournes with a manufacturer part >>>>>> number of 300SP-1-502. Unit cost $7.73 in 2011. I bought 26 so >>>>>> my cost was about $200. I wanted a "Manufactured in America" >>>>>> part but can't remember if that was too pricey or not. >>>> >>>> Tony wrote: >>>> >>>>> They are now $92.55 from Arrow now and Farnell want over $200 each >>>>> if you buy 25 or more!!!! There don't seem to be any obvious cheap >>>>> alternatives for 10 turn 20ppm/C 5W pots. >>>> >>>> The original pots were Bunker Ramo-Eltra (later, Bunker >>>> Ramo-Amphenol) P/N 3800P-502. These were 20-turn, 5k, 10%, 1W, >>>> +/-50 ppm/C wirewound parts in the 34b rectangular package. The >>>> Bourns 3005P-1-502 matches these specifications (I suspect "300SP" >>>> in Charles's message was a typo). I do not know if the pin layout >>>> is the same as the 3800P-502. Verical has the lowest price on the >>>> 3005P-1-502 that I could find in a quick search, $7.68 each. Others >>>> charge from $9 to $14. Tony -- what part number were you quoting >>>> specs and prices for? I >>>> found nothing searching for "300SP-1-502." >>>> >>>> Best regards, >>>> >>>> Charles