https://www.amazon.com/QMseller-Straight-Connector-Coaxial-Adapter/dp/B087RQMKQN/ref=sr_1_15?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-15

https://www.amazon.com/Fairview-Microwave-SCT048-SMA-Connector-Attachment/dp/B08PBCP3LZ/ref=sr_1_8?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-8

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

On Sun, 27 Jun 2021 15:10:25 -0700, jlarkin@highlandsniptechnology.com
wrote:

>
>
>https://www.amazon.com/QMseller-Straight-Connector-Coaxial-Adapter/dp/B087RQMKQN/ref=sr_1_15?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-15
>
>https://www.amazon.com/Fairview-Microwave-SCT048-SMA-Connector-Attachment/dp/B08PBCP3LZ/ref=sr_1_8?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-8

Or

https://www.amazon.com/Female-Solder-Mount-Adapter-Connector/dp/B082S2QWYW/ref=sr_1_83?dchild=1&keywords=sma+microwave+edge+connector&qid=1624832114&sr=8-83

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

On Monday, June 28, 2021 at 8:18:07 AM UTC+10, jla...@highlandsniptechnology.com wrote:
> On Sun, 27 Jun 2021 15:10:25 -0700, jla...@highlandsniptechnology.com
> wrote:
>
> >
> >
> >https://www.amazon.com/QMseller-Straight-Connector-Coaxial-Adapter/dp/B087RQMKQN/ref=sr_1_15?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-15
> >
> >https://www.amazon.com/Fairview-Microwave-SCT048-SMA-Connector-Attachment/dp/B08PBCP3LZ/ref=sr_1_8?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-8
>
> Or
>
> https://www.amazon.com/Female-Solder-Mount-Adapter-Connector/dp/B082S2QWYW/ref=sr_1_83?dchild=1&keywords=sma+microwave+edge+connector&qid=1624832114&sr=8-83

SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?

--
Bill Sloman, Sydney

Am 28.06.21 um 03:44 schrieb Bill Sloman:

>
> SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?

That they are > 10 dB cheaper nowadays than they used to be?

Gerhard

On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
> Am 28.06.21 um 03:44 schrieb Bill Sloman:
> >
> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
> That they are > 10 dB cheaper nowadays than they used to be?

Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.

--
Bill Sloman, Sydney

On Mon, 28 Jun 2021 04:27:07 +0200, Gerhard Hoffmann <dk4xp@arcor.de>
wrote:

>Am 28.06.21 um 03:44 schrieb Bill Sloman:
>
>>
>> SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
>
>
>That they are > 10 dB cheaper nowadays than they used to be?
>
>Gerhard
>

The price ratio is 1800:1.

I don't think you could tell the difference up to 5 GHz or so. Those
cheap Amazon edge-launch SMAs seem to be pretty good.

The center pin tends to be fat, but if you handle the layout right
it's almost invisible on a 20 GHz TDR.

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

Bill Sloman <bill.sloman@ieee.org> wrote:
> On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
>> Am 28.06.21 um 03:44 schrieb Bill Sloman:
>> >
>> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
>> That they are > 10 dB cheaper nowadays than they used to be?
>
> Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.

I think the Chinese gold-colored SMA connectors are stamped, not turned.
Sure the quality is bad, but for many applications it does not matter.

On Monday, June 28, 2021 at 5:53:24 PM UTC+10, Rob wrote:
> Bill Sloman <bill....@ieee.org> wrote:
> > On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
> >> Am 28.06.21 um 03:44 schrieb Bill Sloman:
> >> >
> >> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
> >
> >> That they are > 10 dB cheaper nowadays than they used to be?
> >
> > Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.
>
> I think the Chinese gold-colored SMA connectors are stamped, not turned.
> Sure the quality is bad, but for many applications it does not matter.

SMB and SMC were intended to be the cheaper, lower performance variations of the SMA-sized connector. If you want cheap, it probably isn't a good idea to go for stamped parts that are intended to look like higher-quality parts without delivering the essential dimensional accuracy

--
Bill Sloman, Sydney

On 28 Jun 2021 07:53:17 GMT, Rob <nomail@example.com> wrote:

>Bill Sloman <bill.sloman@ieee.org> wrote:
>> On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
>>> Am 28.06.21 um 03:44 schrieb Bill Sloman:
>>> >
>>> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
>>> That they are > 10 dB cheaper nowadays than they used to be?
>>
>> Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.
>
>I think the Chinese gold-colored SMA connectors are stamped, not turned.
>Sure the quality is bad, but for many applications it does not matter.

I bought some fairly nice fat binding posts in China- the metal part
appears to be cast rather than a screw-machined part. It's good enough
for the purpose.

--
Best regards,
Spehro Pefhany

On Sun, 27 Jun 2021 15:17:58 -0700, jlarkin@highlandsniptechnology.com
wrote:

>On Sun, 27 Jun 2021 15:10:25 -0700, jlarkin@highlandsniptechnology.com
>wrote:
>
>>
>>
>>https://www.amazon.com/QMseller-Straight-Connector-Coaxial-Adapter/dp/B087RQMKQN/ref=sr_1_15?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-15
>>
>>https://www.amazon.com/Fairview-Microwave-SCT048-SMA-Connector-Attachment/dp/B08PBCP3LZ/ref=sr_1_8?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-8
>
>Or
>
>https://www.amazon.com/Female-Solder-Mount-Adapter-Connector/dp/B082S2QWYW/ref=sr_1_83?dchild=1&keywords=sma+microwave+edge+connector&qid=1624832114&sr=8-83
These are useful. There are different models for different PCB
thicknesses. I bought mine from Ebay.

On Monday, June 28, 2021 at 11:50:28 PM UTC+10, Spehro Pefhany wrote:
> On 28 Jun 2021 07:53:17 GMT, Rob <nom...@example.com> wrote:
>
> >Bill Sloman <bill....@ieee.org> wrote:
> >> On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
> >>> Am 28.06.21 um 03:44 schrieb Bill Sloman:
> >>> >
> >>> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
> >>> That they are > 10 dB cheaper nowadays than they used to be?
> >>
> >> Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.
> >
> >I think the Chinese gold-colored SMA connectors are stamped, not turned.
> >Sure the quality is bad, but for many applications it does not matter.
>
> I bought some fairly nice fat binding posts in China- the metal part
> appears to be cast rather than a screw-machined part. It's good enough
> for the purpose.

Precision casting can presumably be made more precise if you throw enough technology at it. It's certainly a lot quicker than machining. Once you get up to GHz frequencies, the critical dimensions of the insides of your connectors are going to have to be pretty precise.

--
Bill Sloman, Sydney

On 28 Jun 2021 07:53:17 GMT, Rob <nomail@example.com> wrote:

>Bill Sloman <bill.sloman@ieee.org> wrote:
>> On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
>>> Am 28.06.21 um 03:44 schrieb Bill Sloman:
>>> >
>>> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
>>> That they are > 10 dB cheaper nowadays than they used to be?
>>
>> Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.
>
>I think the Chinese gold-colored SMA connectors are stamped, not turned.
>Sure the quality is bad, but for many applications it does not matter.

My management makes engineers send a request email to have someone
pull a part from stock for us, which can take 10 minutes, in theory.
So we have a private stock of parts kits and hardware and stuff. I buy
these types of SMA connectors from Amazon, and cables and adapters
too, random brands, and they have always been fine. I TDR them for
high-speed behavior and they are always good. Something that small
almost has to be.

The attenuators can be mediocre.

https://www.dropbox.com/sh/p0lz4zbk4ap77ub/AAAd76ISBuFf5LFCSlLLD2jLa?dl=0

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

On Mon, 28 Jun 2021 17:12:38 +0300, LM <sala.nimi@mail.com> wrote:

>On Sun, 27 Jun 2021 15:17:58 -0700, jlarkin@highlandsniptechnology.com
>wrote:
>
>>On Sun, 27 Jun 2021 15:10:25 -0700, jlarkin@highlandsniptechnology.com
>>wrote:
>>
>>>
>>>
>>>https://www.amazon.com/QMseller-Straight-Connector-Coaxial-Adapter/dp/B087RQMKQN/ref=sr_1_15?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-15
>>>
>>>https://www.amazon.com/Fairview-Microwave-SCT048-SMA-Connector-Attachment/dp/B08PBCP3LZ/ref=sr_1_8?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-8
>>
>>Or
>>
>>https://www.amazon.com/Female-Solder-Mount-Adapter-Connector/dp/B082S2QWYW/ref=sr_1_83?dchild=1&keywords=sma+microwave+edge+connector&qid=1624832114&sr=8-83
>These are useful. There are different models for different PCB
>thicknesses. I bought mine from Ebay.

The hazard with edge-launches is that if the board is a bit too thick,
some connector ground prongs won't fit over the board. 65 mils thick
max on the board, metal-to-metal, seems to be right.

Vbites are great but won't snap on if the board is thick. We remove
the solder mask in the connector area, to save a few mils.

--

John Larkin Highland Technology, Inc

The best designs are necessarily accidental.

On Tuesday, June 29, 2021 at 12:44:19 AM UTC+10, jla...@highlandsniptechnology.com wrote:
> On 28 Jun 2021 07:53:17 GMT, Rob <nom...@example.com> wrote:
> >Bill Sloman <bill....@ieee.org> wrote:
> >> On Monday, June 28, 2021 at 12:27:13 PM UTC+10, Gerhard Hoffmann wrote:
> >>> Am 28.06.21 um 03:44 schrieb Bill Sloman:
> >>> >
> >>> > SMA connectors been around since the late 1980's to my certain knowledge, and probably quite a bit longer. What's your point?
> >>> That they are > 10 dB cheaper nowadays than they used to be?
> >>
> >> Not a point that he made explicitly. SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.
> >
> >I think the Chinese gold-colored SMA connectors are stamped, not turned.
> >Sure the quality is bad, but for many applications it does not matter.
>
> My management makes engineers send a request email to have someone
> pull a part from stock for us, which can take 10 minutes, in theory.
> So we have a private stock of parts kits and hardware and stuff. I buy
> these types of SMA connectors from Amazon, and cables and adapters
> too, random brands, and they have always been fine. I TDR them for
> high-speed behavior and they are always good.

Somebody a bit more careful might not be quite as happy. "Always good" isn't a quantitative assessment.

Impedance discontinuities can be quantified, if you know what you are doing

> Something that small almost has to be.

At a low enough frequency.

> The attenuators can be mediocre.
>
> https://www.dropbox.com/sh/p0lz4zbk4ap77ub/AAAd76ISBuFf5LFCSlLLD2jLa?dl=0

When compared with what?

--
Bill Sloman, Sydney

On Sunday, June 27, 2021 at 8:10:24 PM UTC-7, Bill Sloman wrote:

> ///SMA - with it's turned screw attachment - is never going to be all that cheap. Presumably the market is a lot bigger now than it was in the late 1980's when GHz semiconductors were thinner on the ground, and also rather more expensive.

I suspect the items in question were zinc-cast, and it only takes two operations to precision bore and
thread them; if you can get robots to fit the castings onto carriers, the machining is kinda cheap. Then
it's off to nickel-plate and gold-flash. For cheap BNC, they didn't gold-flash.

Precision machining is required for every ballpoint pen, but... in quantity, that's not a high cost.

On Sunday, June 27, 2021 at 3:10:35 PM UTC-7, jla...@highlandsniptechnology..com wrote:
> https://www.amazon.com/QMseller-Straight-Connector-Coaxial-Adapter/dp/B087RQMKQN/ref=sr_1_15?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-15
>
> https://www.amazon.com/Fairview-Microwave-SCT048-SMA-Connector-Attachment/dp/B08PBCP3LZ/ref=sr_1_8?dchild=1&keywords=sma+microwave+edge+connector&qid=1624831588&sr=8-8

The Fairview has a SWR spec of 1.25:1 up to 27 GHz. The uncertainty is bounded for this portion of mismatch. (Granted, I am presuming that is a max number.) The SWR spec for the "QMseller" is... oh, there is no spec. No bound on the uncertainty. Probably no bound on anything. Maybe a few flakes strip off as you screw the cable on... lol.

I wouldn't say this is apples2apples if comparison is your point.