| Electronics > Repair |
| Wavetek 2520a 0.2-2,200MHz RF sig gen repair |
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| dazz1:
Hi I removed and isolated the main board. That takes about half an hour. I applied power and the positive input power is shorted. None of the +/-15V voltage regulators or caps are warm. It is most likely a shorted cap on the input side of the voltage regulators. I have already replaced 4 but there are plenty more to fail. I have decided to go through and replace all tant caps on the +/-18 volt supply rail. This includes replacing the no-name-brand new tant caps I sourced from the local hobby electronics shop. You may be wondering why I didn't do this from the start. When I started, I didn't know if the 2520a was fixable. It is old enough to include obsolete irreplaceable parts. The eprom code and LCD displays cannot be replaced. Now that I have had the 2520a running for at least a couple of hours before faulting again, I know that it is fixable. I also plan to replace the battery backed ram. At 32 years of age, it should not still be working. I am trying to find someone somewhere who can burn the eproms. That process would give me a backup of the eprom contents. It is going to take me a while to get the parts and complete the install so this topic will probably be silent for a while. Dazz |
| TheDefpom:
How many EPROM's are there? I could only see one from the photos and diagrams you posted, and that was a 27C64. |
| dazz1:
--- Quote from: TheDefpom on June 10, 2021, 09:43:37 am ---How many EPROM's are there? I could only see one from the photos and diagrams you posted, and that was a 27C64. --- End quote --- Hi There are five. 1x 64 and 4x 128. I have not been able to find an accessible eprom programmer. Even if I did, I suspect find a PC that can run the code would be a problem. Dazz |
| tautech:
--- Quote from: dazz1 on June 10, 2021, 10:46:10 am --- --- Quote from: TheDefpom on June 10, 2021, 09:43:37 am ---How many EPROM's are there? I could only see one from the photos and diagrams you posted, and that was a 27C64. --- End quote --- Hi There are five. 1x 64 and 4x 128. I have not been able to find an accessible eprom programmer. Even if I did, I suspect find a PC that can run the code would be a problem. Dazz --- End quote --- Do you have a W10 PC ? If so Defpom and I can make it happen. |
| dazz1:
Hi W 10PC = Windows 10 PC ?? Yes I have several. Code that I wrote for 8086 PCs in the 1980's and 1990's won't run on Win10 without some retro conversion software. Dazz |
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