UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

SATOLEX · 8th Mar 2021, 9:34 pm

Hi, I agree that the resistor has to be 50 Ohms. The reason that you measure 2K is because the gold has no connection to the end anymore with the resistive layer. Probably because it is glued. You can even calculate the resistance value roughly. The square resistance of the resistive layer is about 50 Ohms because it is almost a square. The length of the line from SMA to resistor is about 20 mm and the average width about 0.5 mm. So, 20 mm/0.5 mm is 40 squares which means that the resistance is about 40*50 Ohm = 2000 Ohm

. What do you think?

Regards, Lex

8th Mar 2021, 9:34 pm	#89
SATOLEX Triode Join Date: Feb 2021 Location: Leiden, Zuid-Holland, The Netherlands Posts: 26	Re: Spectrum Analyser TR4172 Hi, I agree that the resistor has to be 50 Ohms. The reason that you measure 2K is because the gold has no connection to the end anymore with the resistive layer. Probably because it is glued. You can even calculate the resistance value roughly. The square resistance of the resistive layer is about 50 Ohms because it is almost a square. The length of the line from SMA to resistor is about 20 mm and the average width about 0.5 mm. So, 20 mm/0.5 mm is 40 squares which means that the resistance is about 40*50 Ohm = 2000 Ohm. What do you think? Regards, Lex