Discussion in 'Amateur Radio Amplifiers' started by N8VUL, Jul 2, 2020.
The specs say the movement is 0-1ma 450 ohm
Take the bad meter out, take the clear cover off, carefully remove the meter scale. You may have to run a razor knife between it and the housing to free it up. Once scale is off look inside you’ll probably see a single tiny resistor burned out. Then carefully check the meter movement with an ohm meter on mid scale like x 10k and see if the meter responds. It should be 300 ohms. If that’s the case just replace the blown resistor.
Oh missed this. Ok meter is bad. Did you find a single resistor inside in series with the movement? Is it blown too? Measure the resistance of that resistor. What is it? Should be 120 ohms. That means the movement is 300 ohms. Order a meter from Ameritron for any of the big 3 amps. Install the resistor and put the 80a scale on it. Fixed
The size of the meter is 3.5 in x 3in. The other amps meters seem to be 2.5x2.5 in.
so far all the advice is good. might have to do a work around on the size of the meter. I am waiting on a reply from PRIME INSTRUMENTS ( maker of the meter) to see if they have a replacement or a rebuild.
What is the size of the panel cut out for the meter. The meter here fits 3 1/4x 2 1/8. The 80a was an offering at the same time as the AL82/1200/1500 I’m pretty sure meters were same size. What size is the panel cut out you have there.
History of Ameritron AL-80 (after Dentron), by Tom W8JI.
You will discover John Moran’s (Prime) involvement in resolving AL-80 issues,
to become AL-80A.
You have good Analog meter repair shops in Cleveland and Detroit.
Depending on damage to meter movement ...
Expect minimum Repair Price to be 1/2 price of New.
Cheap Chinese mfg. , not recommended, with COVID-19 shipment restrictions.
Prime Instruments, is located in Cleveland, originally owned by John Moran, W8IOB (SK).
John was writing amplifier articles before WW2 (Radio, Nov. 1939, page 26)
9805 Walford Ave.
Cleveland, Ohio 44102 USA
16900 Foltz Parkway
Cleveland, OH 44149
RAM Meter has some radio amateurs, on staff.
Ram Meter Inc.
ATTN: Repair Department
1815 Bellaire, Suite B
Royal Oak, MI 48067
Form for Repair Work
https://www.rammeter.com/media/bulletins/Ram Meter Inc Repair-Calibration Request Form1.pdf
Often times buying a meter direct from Ameritron May be cheaper than going to the manufacturer just like buying MFJ stuff is cheaper at the dealer than direct from mfj.
Best I can tell 3.5in wide x 3in tall
Did Prime get back to you on a price for the basic meter? I’m pretty certain the basic meter in the 80A and the big Three are the same basic meter. The 80a has an added resistor. A present day meter for any of the big three should be made to work with the right resistor.