Sinad Meter

[Shadetree Mechanic]

I recently acquired an HP 8656B Signal Generator and am trying to locate a Sinad meter to go with it. Does anyone use a volt meter for this? I have read that a Sinad meter is better, and maybe I am not looking in the right places. There was a guy on Youtube that made some, and I will contact him, but he is in the UK so hoping to find a source state side.

THX!

 

[Pez]

I recently acquired an HP 8656B Signal Generator and am trying to locate a Sinad meter to go with it. Does anyone use a volt meter for this? I have read that a Sinad meter is better, and maybe I am not looking in the right places. There was a guy on Youtube that made some, and I will contact him, but he is in the UK so hoping to find a source state side.

THX!

For what you are doing, I would go with either a genuine a Sinadder (if you can find one), or the the Sinadalizer from the UK, which is pretty much a clone of that circuit.
I have an original Sinadder 3 here, and I prefer to use it over the built in Sinad measurement in my Marconi and HP test sets. You just can't beat that analog meter for Sinad tests, IMHO.
A voltmeter doesn't do what a Sinad meter does. A voltmeter will show a total AF level, including distortion (i.e, how loud it is). A Sinad meter will allow you to see when your RX sensitivity is best, using a built-in 1KHz filter to allow measurement of the distortion and noise in relation to the desired signal. My Sinadder 3 aslo has a voltmeter mode, so you can use it both ways. The built in speaker of the Sinadder 3 is also nice to have.

Motorola also made a nice little Sinad meter back in the day, an R-1013A. Keep an eye open for one of those too.

73

 

[SuperLid]

For what you are doing, I would go with either a genuine a Sinadder (if you can find one), or the the Sinadalizer from the UK, which is pretty much a clone of that circuit.
I have an original Sinadder 3 here, and I prefer to use it over the built in Sinad measurement in my Marconi and HP test sets. You just can't beat that analog meter for Sinad tests, IMHO.
A voltmeter doesn't do what a Sinad meter does. A voltmeter will show a total AF level, including distortion (i.e, how loud it is). A Sinad meter will allow you to see when your RX sensitivity is best, using a built-in 1KHz filter to allow measurement of the distortion and noise in relation to the desired signal. My Sinadder 3 aslo has a voltmeter mode, so you can use it both ways. The built in speaker of the Sinadder 3 is also nice to have.

Motorola also made a nice little Sinad meter back in the day, an R-1013A. Keep an eye open for one of those too.

73

FYI, the Motorola SINAD meter was made for them by Helper so, it is identical to the Sinadder. This is true for a lot of /\/\ branded test equipment.

 

[Pez]

FYI, the Motorola SINAD meter was made for them by Helper so, it is identical to the Sinadder. This is true for a lot of /\/\ branded test equipment.

Ha! That's awesome, I didn't know that.

 

[SuperLid]

Ha! That's awesome, I didn't know that.

I have a Motorola freq counter that was made for them by Heathkit. Their wattmeters were made by Bird.

 

[SuperLid]

Ha! That's awesome, I didn't know that.

I have an old Sinadder here somewhere. I wonder how much dust it has on it now. I need to find it and clean it up!

 

[CbRadiosPRONTO]

eBay item number 326087571757

eBay.com/itm/326087571757

 

[Shadetree Mechanic]

eBay item number 326087571757

eBay.com/itm/326087571757

Thanks, I saw that and was hoping to find a new one. But I took a chance and offered him $185, hopefully it really works.....

 

[brandon7861]

W2AEW has a video of the Sinadder 3. He talks about how it works and shows the block diagram and schematic if you want to build it.

 

[Pez]

Thanks, I saw that and was hoping to find a new one. But I took a chance and offered him $185, hopefully it really works.....

There is alignment information available that is not hard to follow. It is important to align them because there are 2 x capacitors that are used for the 1KHz notch filter, which can move in tolerance over time.

Usually, they can be aligned back to where they need to be with the on-board trimpots. In the case of my Sinadder 3, I had to replace the 2 x caps in the filter section because the trimpot adjustment would not pull it back into line.

Let me know if you need any help with that when you (hopefully) get one. I did this job recently so its pretty fresh in my mind.

 

[CbRadiosPRONTO]

There is alignment information available that is not hard to follow. It is important to align them because there are 2 x capacitors that are used for the 1KHz notch filter, which can move in tolerance over time.

Usually, they can be aligned back to where they need to be with the on-board trimpots. In the case of my Sinadder 3, I had to replace the 2 x caps in the filter section because the trimpot adjustment would not pull it back into line.

Let me know if you need any help with that when you (hopefully) get one. I did this job recently so it’s pretty fresh in my mind.

Yes this. It’s a pretty easy alignment procedure. I found them online for mine.

 

[SuperLid]

Thanks, I saw that and was hoping to find a new one. But I took a chance and offered him $185, hopefully it really works.....

Wow! $220 for that dinosaur? Seems like a lot to me, based on seeing them for peanuts years ago. That is the same unit I have. I dug it out today and cleaned it up a bit. I have not tried it yet, we shall see how it is later on.

 

[Shadetree Mechanic]

Wow! $220 for that dinosaur? Seems like a lot to me, based on seeing them for peanuts years ago. That is the same unit I have. I dug it out today and cleaned it up a bit. I have not tried it yet, we shall see how it is later on.

That does seem like a lot, more than I wanted to pay for an untested unit. Hopefully it is in some kind of usable state, and if I have to fix it, its no worse than buying something from MFJ. Haha!

The seller accepted my offer and Eboogle was so nice as to go ahead and use my credit card to pay for it.....

"We automatically charged your Visa ending in xxxx for this purchase."

Gee thanks a lot Ebunk. I am not sure how I feel about that. I usually use paypal from a different account. Its probably my fault somehow, but I was not expecting that. This is the first thing I have purchaced in over a year. Probably the last.

 

[Shadetree Mechanic]

There is alignment information available that is not hard to follow. It is important to align them because there are 2 x capacitors that are used for the 1KHz notch filter, which can move in tolerance over time.

Usually, they can be aligned back to where they need to be with the on-board trimpots. In the case of my Sinadder 3, I had to replace the 2 x caps in the filter section because the trimpot adjustment would not pull it back into line.

Let me know if you need any help with that when you (hopefully) get one. I did this job recently so its pretty fresh in my mind.

Thanks for the offer. I am eager to get this set up, but I don't have much time to actually sit down and work with it yet. I will let you know what I find.

 

[Shadetree Mechanic]

Look what I found, thanks @Klondike Mike for making the video!