Amplifiers inbound for service are not set on a bench and powered up for a diagnostic session. The key reason is that it is risky because additional damage can result. The upside is that we do not end up spending a lot of time chasing symptoms and do not produce detailed performance failure reports. The downside is that sometimes we do not know exactly what had failed. We do know that is will be 100% + on its return to you!
We do troubleshoot newer systems, but on systems older than 10 years we routinely replace all of the RF power transistors and then add our safety and reliability circuits to protect the hardware form collateral damage. This is a good idea now that the amplifiers are no longer being manufactured. We see charred PC boards and have to restore them. Spare PC boards are hard to find so we add a few components to protect them!
Trouble shooting can be expensive. We have found it to be far more time and cost effective to disassemble the systems and then evaluate the sub-assemblies and rebuild/restore them using new generation high performance components. We maintain a set of replacement sub-assemblies in our inventory. This shortens the turnaround time and you get a better product. The key problems (and others) are normally fixed in our process, including marginal performance shipped by the original manufacturer. Sometimes there are additional issues, but they are generally quick fixes since the core reliability parts have been replaced.
This approach is slightly more expensive as compared to a troubleshoot and repair approach, but the restoration pushes the amplifier back down the aging portion of the reliability curve (see image above) adding years of uninterrupted service to its life. Simply replacing a failed transistor in a matrix of several is risky because how does one tell if the next in line is about to fail? From the end performance we can tell if the amp is healthy or something is wrong. We are adding this type of information to our upgraded website.
You get a 1 year warranty on the entire system and not just the work that we did. We also offer Service upgrade kits for those that would like to install upgraded hardware into working amplifiers. We still provide a 1 year warranty on your work! You will find the amplifiers that we service or you upgrade with our kits to be far more reliable and higher performance. We have also been servicing the console power supplies for Agilent.