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Cleaning Inside Old Radio
I was checking the inside of my Frg-7 and found some dust on the PCB and
components. I would like to clean it off with something. Can anyone please recommend something? Is plain spray on contact cleaner safe to use on the components too? Thanks Lucky |
"Lucky" wrote in message ... I was checking the inside of my Frg-7 and found some dust on the PCB and components. I would like to clean it off with something. Can anyone please recommend something? Is plain spray on contact cleaner safe to use on the components too? You used to be able to buy a spray can that with compressed air that was ejected at a rate safe for circuit boards. Don't know if Radio Shack or any other place has it around any more. Free hint: don't use regular compressed air. I found that out the hard way while I was in college. --Mike L. |
Lucky wrote: I was checking the inside of my Frg-7 and found some dust on the PCB and components. I would like to clean it off with something. Can anyone please recommend something? Is plain spray on contact cleaner safe to use on the components too? Thanks Lucky Go down the makeup aisle in your local pharmacy and find a large size "blusher brush". Handiest little duster in the world. It is soft enough to use on electrical components, but will really do the job. Either blow off disloged dust with your breath, or hold the nozzle attachment of a vacuum cleaner about 2" from the board while dusting it. Spray electrical contact cleaner is available through most large retailers and hardware outlets. RatShack sells it, too, but it's a lot more expensive (for essentially the same product). Tony |
Tony Meloche wrote: Lucky wrote: I was checking the inside of my Frg-7 and found some dust on the PCB and components. I would like to clean it off with something. Can anyone please recommend something? Is plain spray on contact cleaner safe to use on the components too? Thanks Lucky Go down the makeup aisle in your local pharmacy and find a large size "blusher brush". Handiest little duster in the world. It is soft enough to use on electrical components, but will really do the job. Either blow off disloged dust with your breath, or hold the nozzle attachment of a vacuum cleaner about 2" from the board while dusting it. Spray electrical contact cleaner is available through most large retailers and hardware outlets. RatShack sells it, too, but it's a lot more expensive (for essentially the same product). Tony I wouldn't use contact cleaner on anything except switches and pots. Don't spray this stuff on components, especially in the high impedance area of the synthesizer, of you could have a non-functioning radio. If you do use a contact cleaner, use one of the Caig products such as De-Oxit or Pro Gold. If you brush the dust off the circuit boards, make sure that you don't bump any of the trimmer capicators. Pete KE9OA |
"pete ke90a" wrote in message oups.com... Tony Meloche wrote: Lucky wrote: I was checking the inside of my Frg-7 and found some dust on the PCB and components. I would like to clean it off with something. Can anyone please recommend something? Is plain spray on contact cleaner safe to use on the components too? Thanks Lucky Go down the makeup aisle in your local pharmacy and find a large size "blusher brush". Handiest little duster in the world. It is soft enough to use on electrical components, but will really do the job. Either blow off disloged dust with your breath, or hold the nozzle attachment of a vacuum cleaner about 2" from the board while dusting it. Spray electrical contact cleaner is available through most large retailers and hardware outlets. RatShack sells it, too, but it's a lot more expensive (for essentially the same product). Tony I wouldn't use contact cleaner on anything except switches and pots. Don't spray this stuff on components, especially in the high impedance area of the synthesizer, of you could have a non-functioning radio. If you do use a contact cleaner, use one of the Caig products such as De-Oxit or Pro Gold. If you brush the dust off the circuit boards, make sure that you don't bump any of the trimmer capicators. Pete KE9OA Ok I'll be careful. I picked up some stuff this morning from Radio Shack. It's an electronics cleaner. Looks to have ether in it but the brush is stiff. I won't use it on the components even though it says it can used. Was $10.50 a can! Lucky |
pete ke90a wrote:
snip If you brush the dust off the circuit boards, make sure that you don't bump any of the trimmer capicators. Pete KE9OA Reminds me of when I was a kid - my best friend decided to soup up his dad's radio and found the trimmer caps and the slugs in the IF transformers were loose and needed tightening. ;) Any update on the enthusiast's MW radio you were working on? |
HI from Ken,
"Lucky" wrote in message Can anyone please recommend something? Is plain spray on contact cleaner safe to use on the components too? Thanks Lucky The best bet is to use one of the very fine haired wide brushes that your 'XYL' or your 'YL' uses to put on her mak-up. You can obtain them very easily from any cosmetics store. I find a lot of the commercial cleaners leave a residue on the boards and this detracts from they appearance. Hope this helps, cheers, Ken, G4KIR. |
Hi Mark,
All of the RF design is done...........I have built two prototypes. On one of them, I use a ten turn pot to tune the VCO. The other unit uses a PLL for tuning. I think we will have some time to develop the tuning software, etc. We were tied up with a big project for the last several months; this was the Automark election machine that you may have heard about in the news. All kinds of fun things, getting it through EMC certification. Speaking of MW receivers, I did purchase the Boston Acoustics Receptor clock radio. MW performance is not bad, but the selectivity is pretty wide. It appears to be a single conversion affair that uses a 450kHz I.F. It might be a double conversion unit, but when I peaked the Radio Shack loop antenna on the image frequency, I was able to receive the image. It could also be that the (2 X 2nd I.F.) rejection isn't too good, if this is truly a double conversion unit. Is it worth the 150 dollars? Could be. I did call up Boston Acoustics to see if I could get ahold of some service information. The wouldn't make it available. When I asked them how to remove the main circuit board from the unit so that I could change the 450kHz filter, they explained that they couldn't give me that information, since I if were electrocuted, they would be liable. When I explained that I was going to quote them in my review, they said that it was ok. If anybody figures out how to get this thing apart, feel free to contact me. Oh, another thing............it could be off topic, but this is good for you Drake '7 line folks. If you change the 1st mixer in your Drake R7/TR7 to a Mini-Circuits SRA-3MH (Level 13) mixer, and you change the 1N4148s in the 2nd mixer to matched sets of 1N5711 hot carrier diodes, the receive performance improves a bit. The original 1st mixer has an SSB conversion loss of 6.5dB, while the Mini-Circuits mixer has a conversion loss of 4.75dB. As far as the 2nd mixer, it is good to get rid of those general purpose switching diodes and replace them; the 1N5711 Hot Carrier diodes have lower loss, better IM characteristics, and they are designed for RF applications. One thing about that Radio Shack cleaner. I have used some of it in the past, and it has dissolved plastic switch wafers. I would stay away from that. The Caig De-Oxit is in the same price range, and it doesn't destroy components. In the old days, we used to use Freon based solvents to clean circuit boards. I would get ahold of the De-Oxit and play it safe. Caig is the same company that marketed a product called Tweak. Pete "Mark S. Holden" wrote in message ... pete ke90a wrote: snip If you brush the dust off the circuit boards, make sure that you don't bump any of the trimmer capicators. Pete KE9OA Reminds me of when I was a kid - my best friend decided to soup up his dad's radio and found the trimmer caps and the slugs in the IF transformers were loose and needed tightening. ;) Any update on the enthusiast's MW radio you were working on? |
Pete KE9OA wrote:
As far as the 2nd mixer, it is good to get rid of those general purpose switching diodes and replace them; the 1N5711 Hot Carrier diodes have lower loss, better IM characteristics, and they are designed for RF applications. Is the 1N5711 a good substitute for the 1SS135? |
According to
http://www.geocities.co.jp/SiliconVa...v-di.htm#mixer the 1SS135 appears to be a VHF/UHF switching diode, from Rohm Semiconductors. It could be a good diode, but I know that the 5711 is intended for mixer/detector service. I was unable to find a data sheet for the 135, so I can't make direct comparisons. I have used the 5711 over the past several years, with good results. Awhile back, I picked up a batch of matched quad sets of these diodes from the Rockwell-Collins Inventory Disposal store for around a dollar a pound. Too bad I got rid of most of them.........................I thought I would be living out there for longer than I did. Easy to take things for granted, when they are plentiful. Fortunately, these things are currently available, and they aren't too expensive. Pete "starman" wrote in message ... Pete KE9OA wrote: As far as the 2nd mixer, it is good to get rid of those general purpose switching diodes and replace them; the 1N5711 Hot Carrier diodes have lower loss, better IM characteristics, and they are designed for RF applications. Is the 1N5711 a good substitute for the 1SS135? |
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