I have the 53132A/050 with poor sensitivity. The CLIP for this product does not have the schematic for this assembly. 53132-60013. I have a defective 2nd stage amplifier and 3rd stage amplifier. 2nd stage is not conducting, shorted. Third stage has low gain and was replaced before. However, the repair person did a horrible job, which is reason for the early failure again. Is it possible to get the schematic for this assembly. Or even the P/N's for the amplifiers to replace them.