-
You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
-
A Winner has been selected for the 2025 Radioddity Cyber Monday giveaway! Click Here to see who won!
Radio Shack 21-524SWR/Watt Meter MOD
- Thread starter AudioShockwav
- Start date
I have no idea how accurate it will be, but this is similar to what a lot of the manufactures do to there meters and then call them pep reading.
The only way to get even close to "true"pep measurement is to use a meter with "active pep reading circuity" built into the meter.
This would require a power source in the meter, like a bird meter with a kit added to it that uses 9 volts to power the circuit.
Not sure if R/S will have a .33 ceramic disc capacitor, but a electronic supply place should have them.
All it is going to do is show swing swing swing, i found this in a old modification book I picked up at a yard sale this weekend.
73
Jeff
The only way to get even close to "true"pep measurement is to use a meter with "active pep reading circuity" built into the meter.
This would require a power source in the meter, like a bird meter with a kit added to it that uses 9 volts to power the circuit.
Not sure if R/S will have a .33 ceramic disc capacitor, but a electronic supply place should have them.
All it is going to do is show swing swing swing, i found this in a old modification book I picked up at a yard sale this weekend.
73
Jeff
When I look up 33MFD 100v caps it shows soooo many different types. I'm a dummy when it comes to finding the right one. I can put it in no problem.
Is there another way it is described???
Thanks Wav
God Bless
Is there another way it is described???
Thanks Wav
God Bless
Call Mouser
1800 346 6873
Tell them you need a . 33 micro farad, 100 volt ceramic disc capacitor.
Should be less than a buck and they can ship it in an envelope.
I do not think they have a minimum.
73
Jeff
1800 346 6873
Tell them you need a . 33 micro farad, 100 volt ceramic disc capacitor.
Should be less than a buck and they can ship it in an envelope.
I do not think they have a minimum.
73
Jeff
It's not "33 MFD". It should be 0.33 (POINT three three) MFD. Which should be a LOT easier to find.
You are correct, that is what I posted . 33, and if you click the picture it will expand, and you can see that it also says . 33.
73
Jeff
73
Jeff
It still won't show true peak power. My Diamond meter which is head and shoulders above the R/S meter still does not read true peak power even in the pep position. The manual even states that the meter will only read about 70-80% of true peak when in pep mode.ONLY a meter with a powered peak sample-and-read circuit will show true pep.
BTW, the value of the capacitor should not be all that critical as all it does is charge up on peaks and holds the value a bit higher. In fact the higher the value the higher the meter may show and the meter action will be slower to decay.
BTW, the value of the capacitor should not be all that critical as all it does is charge up on peaks and holds the value a bit higher. In fact the higher the value the higher the meter may show and the meter action will be slower to decay.
will this mod work on the new Model:
21-534
| Catalog #: 21-534
meters?
is the cap there to hold the needle for a second or two so u can slowly take your time looking at the meter needle ?
i just found a couple dozen of .33 µF disk caps in the out of control unorganized drawer.
21-534
| Catalog #: 21-534
meters?
is the cap there to hold the needle for a second or two so u can slowly take your time looking at the meter needle ?
i just found a couple dozen of .33 µF disk caps in the out of control unorganized drawer.
One question...is this mod for fairly recent build of this SWR/power meter?
I ask b/c I had one of these I bought in 2007, it would read swing ok. I even used it to check a 2 pill linear amp and it showed 200 + watts.
I sold it and just bought a new one, and it only shows up to 25 watts of swing on what is supposed to be an 80 watt radio (Magnum 257HP). It doesn't matter if I'm on AM, USB or LSB, doesn't matter if the mic gain is all the way up and the RF power is all the way CW, whistle in the mic or go aaaauuudddiiooo....25-30 watts on the meter is all I get.
I ask b/c I had one of these I bought in 2007, it would read swing ok. I even used it to check a 2 pill linear amp and it showed 200 + watts.
I sold it and just bought a new one, and it only shows up to 25 watts of swing on what is supposed to be an 80 watt radio (Magnum 257HP). It doesn't matter if I'm on AM, USB or LSB, doesn't matter if the mic gain is all the way up and the RF power is all the way CW, whistle in the mic or go aaaauuudddiiooo....25-30 watts on the meter is all I get.
I would say that a new one has the cap
I would say that a new one has the cap as it has a peak setting. I remember mine showed 70% of true peak when new and as it aged- about 12 years, it would not show peak readings very well anymore. Good meter for the current retail price of under $40 now at your local Shack, but it has no features other than SWR and power (AVG and PEAK switchable) up to 2000 watts. And you get the generic Radio Shack look to go with it.
I would say that a new one has the cap as it has a peak setting. I remember mine showed 70% of true peak when new and as it aged- about 12 years, it would not show peak readings very well anymore. Good meter for the current retail price of under $40 now at your local Shack, but it has no features other than SWR and power (AVG and PEAK switchable) up to 2000 watts. And you get the generic Radio Shack look to go with it.