Date   

Re: SA612AN - really hot when VCC is applied

Richard Seguin
 

Hi Chris,

Thank you for passing this along. I am getting 50M ohm between 2 and 3 and
nothing on the reverse. The other pins yield similar results. I get values
that are way off the mark or none at all.

I'll keep them around until I can get a good batch and I'll see how they
compare, for now, I'm marking them as being counterfeit.

Richard (VE9IT)

On Mon, Sep 24, 2018 at 1:52 PM Chris Smith <me@m0xte.uk> wrote:

Hi,

Quick update on this. I was contacted off list with measurements on
another NE602AN. If you swap the probes round on pin pairs 1,3 and 2,3
this drops to around 4.7M so clearly this is activating a semiconductor
junction inside the device.
7 -> 3 = 25k 1 -> 3 = 9.86M ohms 2 -> 3 = 9.73M ohms 6 -> 4 = 19.5k 6
-> 5 = 19.5k
That should be enough to do a simple red/green test on a 612/602 to see
if it is actually one or not.
Many thanks to the additional contributor :)

Best regards,

Chris Smith M0XTE

On Sun, 23 Sep 2018, at 20:56, Chris Smith wrote:
Sounds like they are hooky. This is happening very frequently with
popular parts. Get one out and measure the following with a DMM
on ohms.> From the datasheet there should be the following approximate
resistances> between the pins:
7 -> 3 = 25k
1 -> 3 = 1.5k
2 -> 3 = 1.5k
6 -> 4 = 19.5k
6 -> 5 = 19.5k

If all of these are vastly off then it's probably not a 612.

Finding out what it really is could be interesting :)

Best regards,

Chris Smith M0XTE


On Sun, 23 Sep 2018, at 20:51, Richard Seguin wrote:
Hello folks,

I'm experiencing a very fishy situation with a batch of NE612AN
double> balanced mixers that I got from China. When I apply power to>>
the correct> pin (I verified several times) they get really hot to
the touch.>> I created> a test circuit that is similar to what the
datasheet
specifies for an> unbalanced input, and I have also played around
with using a crystal>> oscillator instead of the DDS output that I
wanted to use.

I'm not looking for anyone to troubleshoot my circuit, I'm
more or less> curious if anyone else ran into symptoms like
this. I'm>> suspecting that> what I have may not be SA612AN mixers,
and that I am
applying>> power to the> incorrect pins.

If anyone has one of these laying around, what happens when you
apply VCC> (5V) to pin 8 and GND to pin 3? Does the IC heat up?

Richard (VE9IT)







--
Richard


Re: OCXO OSC5A2B02 10.000 MHZ

Graham, VE3GTC
 

Good question and my best answer is that it depends on the particalar
device and whether there is an internal regulator (i.e. 5v to 3.3V or
similar) and how good that internal regulator is.

I found some data for this device:

http://www.cti.ac.cn/Products/system/Professional/crystal/2013/0725/289.html

Use google translate.

Power is spec'ed at 5.0V +/- 5% and control V range as 2.0V +/- 2.0V
(that is 2v nominal with a range of + and - 2v from nominal i.e. 0 to +4
)

Like all precision devices, the better regulation the better the results.
Any noise or irregularities in the supply could result in excessive
phase noise and variations in your reference.

cheers, Graham ve3gtc

On 9/24/2018, "Alan Jones" <oalanjones@gmail.com> wrote:

Hi Graham,
Thanks for confirming the operation of the OCXO.
How critical is 5 volt precision in using the OCXO?

Al

On Mon, 24 Sep 2018 10:16:38 -0400, Graham <planophore@aei.ca> wrote:

Al,

Your brief description of the operation of your OCXO sounds like a
typical OCXO - higher current at start up til stabilization, then lower
current draw. Same goes for the frequency drift.

The adjustment only needs a potentiometer to be used as a voltage divider
and is not overly critical as far as value is concerned. I tend to use
something around 5k.

There is often a Vref output from OCXO that you would use on one side of
the pot rather than the VCC, the other side of the pot to ground, and
the wiper to the ADJ.

Don't expect a lot of adjustment range, on the order of single digit Hz
+/- of the nominal frequency

cheers, Graham ve3gtc


On 9/24/2018, "Alan Jones" <oalanjones@gmail.com> wrote:

I finally received a OCXO from the extremely slow boat from China.
How much resistance do I need in order to adjust "Vcont" on pin #3 ?

My initial hook up without Vcont, according to my eBay 8 digit frequency
counter showed a slow frequency drift from about 9.999.820 MHz up to
10.000.027 and stabilized after about 7 minutes. Current draw got up to
a
max of around 400 mA and then settled in around 198 mA and the
oscillator
can was warm to the touch.

The OCXO I received from eBay was used and has a calibration sticker on
it.

While looking for info on this OCXO I stumbled onto this document about
Precision Oscillator Overview.
http://freqelec.com/oscillators/osc_overview_4-07.pdf

I just ordered the GPSDO that Chuck referenced in an earlier email.
We will see how long it takes to get here!

Al, N8WQ




Re: WWVB surrogate

Pete Ferrand
 

Another approach I'd like to try is an IOS app called Clock Wave. It picks up the time from the net, then emits a tone from the iPhone/iPad/iPod that is picked up by your radio controlled watch/clock. Probably works thru harmonics from the mobile devices speaker. It's been on the app store for two years and amazingly enough appears to work really well. The cost is a not unreasonable $1.99. Unfortunately I don't have any Apple devices - it needs IOS 8 or later - so I can't use it.

Listing:

https://itunes.apple.com/us/app/clock-wave/id1073576068?mt=8

Various YouTube demos and discussions can be found with a search.

Regrettably it doesn't seem as though there's anything like this for Android or Windows.

Pete
WB2QLL
Mount Pleasant, WI


Re: WWVB surrogate

Dave Hartman <ac2gl@...>
 

Have you taken a look at:
http://cwtd.org/CWTD_GPSDO/index.html
73 Dave


Re: SA612AN - really hot when VCC is applied

Chris Smith <me@...>
 

Hi,

Quick update on this. I was contacted off list with measurements on
another NE602AN. If you swap the probes round on pin pairs 1,3 and 2,3
this drops to around 4.7M so clearly this is activating a semiconductor
junction inside the device.
7 -> 3 = 25k 1 -> 3 = 9.86M ohms 2 -> 3 = 9.73M ohms 6 -> 4 = 19.5k 6
-> 5 = 19.5k
That should be enough to do a simple red/green test on a 612/602 to see
if it is actually one or not.
Many thanks to the additional contributor :)

Best regards,

Chris Smith M0XTE

On Sun, 23 Sep 2018, at 20:56, Chris Smith wrote:
Sounds like they are hooky. This is happening very frequently with
popular parts. Get one out and measure the following with a DMM
on ohms.> From the datasheet there should be the following approximate
resistances> between the pins:
7 -> 3 = 25k
1 -> 3 = 1.5k
2 -> 3 = 1.5k
6 -> 4 = 19.5k
6 -> 5 = 19.5k

If all of these are vastly off then it's probably not a 612.

Finding out what it really is could be interesting :)

Best regards,

Chris Smith M0XTE


On Sun, 23 Sep 2018, at 20:51, Richard Seguin wrote:
Hello folks,

I'm experiencing a very fishy situation with a batch of NE612AN
double> balanced mixers that I got from China. When I apply power to>> the correct> pin (I verified several times) they get really hot to
the touch.>> I created> a test circuit that is similar to what the datasheet
specifies for an> unbalanced input, and I have also played around
with using a crystal>> oscillator instead of the DDS output that I wanted to use.

I'm not looking for anyone to troubleshoot my circuit, I'm
more or less> curious if anyone else ran into symptoms like
this. I'm>> suspecting that> what I have may not be SA612AN mixers, and that I am
applying>> power to the> incorrect pins.

If anyone has one of these laying around, what happens when you
apply VCC> (5V) to pin 8 and GND to pin 3? Does the IC heat up?

Richard (VE9IT)





Re: WWVB surrogate (was: Update on GPSDO video)

Ray
 

sarma, you are correct. I notice about a one second delay between my computer clock and WWV even immediately after a NIST itnternet sync. But I guess one second is good enough for us humans.

My watch is virtually dead on with WWV since is syncs with WWVB. WWVB covers most of North America and parts of South America depending on time of day.

https://tf.nist.gov/stations/wwvbcoverage.htm

Ray,
AB7HE


Re: OCXO OSC5A2B02 10.000 MHZ

Ray
 

I purchased this one:
https://www.ebay.com/itm/1-USED-CETC-CTI-OSC5A2B02-10MHz-5V-26-26-12-Square-Wave-OCXO-Crystal-Oscillator/332389156868?hash=item4d63f00804:g:5VIAAOSwruVZxm6k

I took a 5K pot, connected high side to +5V, low side to GND, wiper to the control pin. I let the OXCO warm up for a couple of hours. Using a rubidium standard, I calibrated my frequency counter to 10.000000 MHz. I then connected the OCXO to the counter and adjusted the pot to 10.000000 MHz. I initially tried a 10K pot but it was critical to adjust which is why I went to 5K.

I could have used my scope in XY mode like Chuck does, but it is packed away and I didn't want to dig it out.

Ray,
AB7HE


Re: OCXO OSC5A2B02 10.000 MHZ

Alan Jones
 

Hi Graham,
Thanks for confirming the operation of the OCXO.
How critical is 5 volt precision in using the OCXO?

Al

On Mon, 24 Sep 2018 10:16:38 -0400, Graham <planophore@aei.ca> wrote:

Al,

Your brief description of the operation of your OCXO sounds like a
typical OCXO - higher current at start up til stabilization, then lower
current draw. Same goes for the frequency drift.

The adjustment only needs a potentiometer to be used as a voltage divider
and is not overly critical as far as value is concerned. I tend to use
something around 5k.

There is often a Vref output from OCXO that you would use on one side of
the pot rather than the VCC, the other side of the pot to ground, and
the wiper to the ADJ.

Don't expect a lot of adjustment range, on the order of single digit Hz
+/- of the nominal frequency

cheers, Graham ve3gtc


On 9/24/2018, "Alan Jones" <oalanjones@gmail.com> wrote:

I finally received a OCXO from the extremely slow boat from China.
How much resistance do I need in order to adjust "Vcont" on pin #3 ?

My initial hook up without Vcont, according to my eBay 8 digit frequency
counter showed a slow frequency drift from about 9.999.820 MHz up to
10.000.027 and stabilized after about 7 minutes. Current draw got up to a
max of around 400 mA and then settled in around 198 mA and the oscillator
can was warm to the touch.

The OCXO I received from eBay was used and has a calibration sticker on it.

While looking for info on this OCXO I stumbled onto this document about
Precision Oscillator Overview.
http://freqelec.com/oscillators/osc_overview_4-07.pdf

I just ordered the GPSDO that Chuck referenced in an earlier email.
We will see how long it takes to get here!

Al, N8WQ


Re: WWVB surrogate (was: Update on GPSDO video)

Mvs Sarma <mvssarma@...>
 

If the NIST signals are traveling on OF cables to reach you thro'
internet, perhaps there could be variations and sync'ing might not be that
easy, I fear.
Regards
sarma
vu3zmv

On Mon, Sep 24, 2018 at 8:03 PM Graham <planophore@aei.ca> wrote:

Ed Nisley published an series of articles in Circuit Cellar Ink about
WWVB clocks. Feb 2010 was part 1 and detailed a WWVB simulator.

A quick search using Google will find a number of the WWVB simulator
results including some based on the ubiquitous Arduino.

This is an interesting topic on it's own.

cheers, Graham ve3gtc

On 9/24/2018, "Nick Kennedy" <kennnick@gmail.com> wrote:

That's a crazy enough idea to be a fun project. Be your own private NIST /
WWVB.

I did a PIC program a while ago to decode the data stream from a WWVB
module and have it update a clock, using a PIC.

Going the opposite way, you'd have to figure out how to do that
phase-shifty modulation scheme it uses.

72-

Nick, WA5BDU


On Sun, Sep 23, 2018 at 1:05 PM sigcom1 <sigcom@juno.com> wrote:

Funny, I was thinking almost exactly the same thing about a week ago
when
3 of my 4 WWVB-disciplined clocks refused to sync to NIST for
several days (only 1 remains recalcitrant at the moment).

With the future availability of those signals in question, it's 'time'
(ahem) to consider a GPS disciplined replacement, IMHO.

Faraday cage? I'll just call mine an Incidental Radiator. The trick is
to get my clocks to listen during daylight hours instead of
midnight as they do now ;-P .

73.......Steve Smith WB6TNL

On Sat, Sep 22, 2018 at 7:47 PM chuck adams <chuck.adams.k7qo@gmail.com
wrote:

Any one have the serial output data for the GPSDO? Might be interesting
to build a
1mW transmitter to emulate WWVB and feed my atomic clocks during the
daylight
hours from time to time. Of course, keeping it in a Faraday cage.









Re: WWVB surrogate (was: Update on GPSDO video)

Graham, VE3GTC
 

Ed Nisley published an series of articles in Circuit Cellar Ink about
WWVB clocks. Feb 2010 was part 1 and detailed a WWVB simulator.

A quick search using Google will find a number of the WWVB simulator
results including some based on the ubiquitous Arduino.

This is an interesting topic on it's own.

cheers, Graham ve3gtc

On 9/24/2018, "Nick Kennedy" <kennnick@gmail.com> wrote:

That's a crazy enough idea to be a fun project. Be your own private NIST /
WWVB.

I did a PIC program a while ago to decode the data stream from a WWVB
module and have it update a clock, using a PIC.

Going the opposite way, you'd have to figure out how to do that
phase-shifty modulation scheme it uses.

72-

Nick, WA5BDU


On Sun, Sep 23, 2018 at 1:05 PM sigcom1 <sigcom@juno.com> wrote:

Funny, I was thinking almost exactly the same thing about a week ago when
3 of my 4 WWVB-disciplined clocks refused to sync to NIST for
several days (only 1 remains recalcitrant at the moment).

With the future availability of those signals in question, it's 'time'
(ahem) to consider a GPS disciplined replacement, IMHO.

Faraday cage? I'll just call mine an Incidental Radiator. The trick is
to get my clocks to listen during daylight hours instead of
midnight as they do now ;-P .

73.......Steve Smith WB6TNL

On Sat, Sep 22, 2018 at 7:47 PM chuck adams <chuck.adams.k7qo@gmail.com>
wrote:

Any one have the serial output data for the GPSDO? Might be interesting
to build a
1mW transmitter to emulate WWVB and feed my atomic clocks during the
daylight
hours from time to time. Of course, keeping it in a Faraday cage.







Re: OCXO OSC5A2B02 10.000 MHZ

Graham, VE3GTC
 

Al,

Your brief description of the operation of your OCXO sounds like a
typical OCXO - higher current at start up til stabilization, then lower
current draw. Same goes for the frequency drift.

The adjustment only needs a potentiometer to be used as a voltage divider
and is not overly critical as far as value is concerned. I tend to use
something around 5k.

There is often a Vref output from OCXO that you would use on one side of
the pot rather than the VCC, the other side of the pot to ground, and
the wiper to the ADJ.

Don't expect a lot of adjustment range, on the order of single digit Hz
+/- of the nominal frequency

cheers, Graham ve3gtc

On 9/24/2018, "Alan Jones" <oalanjones@gmail.com> wrote:

I finally received a OCXO from the extremely slow boat from China.
How much resistance do I need in order to adjust "Vcont" on pin #3 ?

My initial hook up without Vcont, according to my eBay 8 digit frequency
counter showed a slow frequency drift from about 9.999.820 MHz up to
10.000.027 and stabilized after about 7 minutes. Current draw got up to a
max of around 400 mA and then settled in around 198 mA and the oscillator
can was warm to the touch.

The OCXO I received from eBay was used and has a calibration sticker on it.

While looking for info on this OCXO I stumbled onto this document about
Precision Oscillator Overview.
http://freqelec.com/oscillators/osc_overview_4-07.pdf

I just ordered the GPSDO that Chuck referenced in an earlier email.
We will see how long it takes to get here!

Al, N8WQ


OCXO OSC5A2B02 10.000 MHZ

Alan Jones
 

I finally received a OCXO from the extremely slow boat from China.
How much resistance do I need in order to adjust "Vcont" on pin #3 ?

My initial hook up without Vcont, according to my eBay 8 digit frequency counter showed a slow frequency drift from about 9.999.820 MHz up to 10.000.027 and stabilized after about 7 minutes. Current draw got up to a max of around 400 mA and then settled in around 198 mA and the oscillator can was warm to the touch.

The OCXO I received from eBay was used and has a calibration sticker on it.

While looking for info on this OCXO I stumbled onto this document about Precision Oscillator Overview.
http://freqelec.com/oscillators/osc_overview_4-07.pdf

I just ordered the GPSDO that Chuck referenced in an earlier email.
We will see how long it takes to get here!

Al, N8WQ


SA612AN Temperature Rise Example

Chuck Carpenter <w5usj@...>
 

Here's a brief example of temperature rise with two SA612s. One in DC RX with external oscillator, the other in DC RX and internal oscillator.

Pin 8 Vcc 5.97 Vdc, 83 deg, after 5 min 89 deg. Ext Osc.

Pin 8 Vcc 5.46 Vdc, 84 deg, after 5 min 86 deg, Int Osc.


Both devices open on the bench.



Chuck Carpenter, W5USJ
EM22cv, Rains Co. TX


Re: SA612AN - really hot when VCC is applied

Mvs Sarma <mvssarma@...>
 

People say that smd parts are more genuine on ebay etc than through hole
parts, and so we can be safe.

On Mon, Sep 24, 2018 at 4:16 PM Mvs Sarma <mvssarma@gmail.com> wrote:

I used to by from one seller.
as I searched now I get the ebay item 362255962960

please search
this guy is genuine


On Mon, Sep 24, 2018 at 3:11 PM Mvs Sarma <mvssarma@gmail.com> wrote:

I think it is 2.45 each at 10 lot and NOT a lot total price.



On Mon, Sep 24, 2018 at 2:13 PM Shirley Dulcey KE1L <mark@buttery.org>
wrote:

I don't think anybody has said that the surface mount SA602 and SA612
parts are scarce. They're still in production and readily available
from distributors.

What is getting scarce is the through-hole version. NXP (successor to
Signetics and Philips) stopped making them a while ago and supplies
are drying up. Diz still has them for now, as does the Switch and
Parts Store (WB9KZY). The Elecraft KX1 switched to using an SMD mixer
and an adapter board before it went out of production, and I suspect
the K2 has done that as well. Generic 8-SOIC to 8-PDIP adapter boards
are available from many sources. One example is the SparkFun
BOB-13655, which is $2.95 for a board that's actually four break-apart
adapters. Another example is the Adafruit 1212: $2.95 for a six pack
of boards. You also need headers; the inexpensive snap-apart ones will
work just fine. I have also seen adapters from Schmartboard and
generic ones for sale at hamfests.

The chip on many of the 8-SOIC adapters is rotated 90 degrees from the
position of the adapter. Make sure to point everything the right way.

One downside of using adapters is that the bypass capacitors are
farther away from the chip. If that turns out to be a problem you can
try putting an SMD bypass cap on the adapter board.

If you get desperate, the NTE7164 is an SA602-compatible part. But you
won't enjoy the price tag.

Although MSOP adapters also exist, don't try to use one with an
Si5351A. That chip is fussy about the lead lengths of its bypass
capacitor and crystal. A much better idea is to use an Si5351A
breakout board; they are available from Adafruit, QRP Labs, and
Etherkit.

It appears that some opportunists are selling counterfeit parts. Be
wary of SA602 and SA612 DIPs (or the older NE602 and NE612 if anybody
offers those) from eBay and Ali Express.
On Mon, Sep 24, 2018 at 1:03 AM Michael <pixelwaster@gmail.com> wrote:

Arrow.com has smd SA612 for $1.66 each. Minimum of 1 ordered with free
overnight shipping. They do ship overnight on a few parts! The next
break points are at 10/1.4988, 100/1.3005, 1000/1.008
The date code is 1708 from Thailand and they have 1900 in stock.
If you are willing to wait three day you can get the parts form the
Netherlands dated 1827. Still free shipping.

Michael
N9XYP

On 9/23/2018 10:17 PM, na5n_qrp wrote:

Kits and Parts (Diz) also has the thru-hole versions shown on his
website ... the NE602AN and NE612AN, as well as the SA602AD SMT
part.
5 for $10, or $2 each. Mouser also has the SMD versions for $2.88/1
and $2.45/10 with 11,000 in stock. DigiKey has them as well for
$2.36
each with 1,000 in stock. Search for SA602 or SA612 ... NE602/612
produces no results and seldom shown in their catalogs, but they
have
them. They're not as rare as some have claimed.







Re: SA612AN - really hot when VCC is applied

Mvs Sarma <mvssarma@...>
 

I used to by from one seller.
as I searched now I get the ebay item 362255962960

please search
this guy is genuine

On Mon, Sep 24, 2018 at 3:11 PM Mvs Sarma <mvssarma@gmail.com> wrote:

I think it is 2.45 each at 10 lot and NOT a lot total price.



On Mon, Sep 24, 2018 at 2:13 PM Shirley Dulcey KE1L <mark@buttery.org>
wrote:

I don't think anybody has said that the surface mount SA602 and SA612
parts are scarce. They're still in production and readily available
from distributors.

What is getting scarce is the through-hole version. NXP (successor to
Signetics and Philips) stopped making them a while ago and supplies
are drying up. Diz still has them for now, as does the Switch and
Parts Store (WB9KZY). The Elecraft KX1 switched to using an SMD mixer
and an adapter board before it went out of production, and I suspect
the K2 has done that as well. Generic 8-SOIC to 8-PDIP adapter boards
are available from many sources. One example is the SparkFun
BOB-13655, which is $2.95 for a board that's actually four break-apart
adapters. Another example is the Adafruit 1212: $2.95 for a six pack
of boards. You also need headers; the inexpensive snap-apart ones will
work just fine. I have also seen adapters from Schmartboard and
generic ones for sale at hamfests.

The chip on many of the 8-SOIC adapters is rotated 90 degrees from the
position of the adapter. Make sure to point everything the right way.

One downside of using adapters is that the bypass capacitors are
farther away from the chip. If that turns out to be a problem you can
try putting an SMD bypass cap on the adapter board.

If you get desperate, the NTE7164 is an SA602-compatible part. But you
won't enjoy the price tag.

Although MSOP adapters also exist, don't try to use one with an
Si5351A. That chip is fussy about the lead lengths of its bypass
capacitor and crystal. A much better idea is to use an Si5351A
breakout board; they are available from Adafruit, QRP Labs, and
Etherkit.

It appears that some opportunists are selling counterfeit parts. Be
wary of SA602 and SA612 DIPs (or the older NE602 and NE612 if anybody
offers those) from eBay and Ali Express.
On Mon, Sep 24, 2018 at 1:03 AM Michael <pixelwaster@gmail.com> wrote:

Arrow.com has smd SA612 for $1.66 each. Minimum of 1 ordered with free
overnight shipping. They do ship overnight on a few parts! The next
break points are at 10/1.4988, 100/1.3005, 1000/1.008
The date code is 1708 from Thailand and they have 1900 in stock.
If you are willing to wait three day you can get the parts form the
Netherlands dated 1827. Still free shipping.

Michael
N9XYP

On 9/23/2018 10:17 PM, na5n_qrp wrote:

Kits and Parts (Diz) also has the thru-hole versions shown on his
website ... the NE602AN and NE612AN, as well as the SA602AD SMT part.
5 for $10, or $2 each. Mouser also has the SMD versions for $2.88/1
and $2.45/10 with 11,000 in stock. DigiKey has them as well for $2.36
each with 1,000 in stock. Search for SA602 or SA612 ... NE602/612
produces no results and seldom shown in their catalogs, but they have
them. They're not as rare as some have claimed.





Re: SA612AN - really hot when VCC is applied

Chris Smith <me@...>
 

Agree on all counts. Worth looking on Aliexpress though as most of the
cheap adapter boards are sourced from that direction anyway.
Possibly a diversion away from the point, but at this point in time I'm
loathed to invest any time in anything that isn't SMD and a modern
design now. Getting slightly tired of chasing down highly in demand
parts which are drying up rapidly and being taken advantage of by
scammers. Nearly all the classic parts and a hell of a lot of really
good new ones are still available from respectable distributors in SMD
form on that side of the fence too.
I reckon you could put together a fully SMD norcal 40A with a Si5351A
replacing the VFO and BFO oscillators and integrating a keyer for less
size and cost than a TH one for example, although that might be treading
on the toes of the K1 a little bit :)
Best regards,

Chris Smith M0XTE

On Mon, 24 Sep 2018, at 09:43, Shirley Dulcey KE1L wrote:
I don't think anybody has said that the surface mount SA602 and SA612> parts are scarce. They're still in production and readily available
from distributors.

What is getting scarce is the through-hole version. NXP (successor to> Signetics and Philips) stopped making them a while ago and supplies
are drying up. Diz still has them for now, as does the Switch and
Parts Store (WB9KZY). The Elecraft KX1 switched to using an SMD mixer> and an adapter board before it went out of production, and I suspect
the K2 has done that as well. Generic 8-SOIC to 8-PDIP adapter boards> are available from many sources. One example is the SparkFun
BOB-13655, which is $2.95 for a board that's actually four break-apart> adapters. Another example is the Adafruit 1212: $2.95 for a six pack
of boards. You also need headers; the inexpensive snap-apart ones will> work just fine. I have also seen adapters from Schmartboard and
generic ones for sale at hamfests.

The chip on many of the 8-SOIC adapters is rotated 90 degrees from the> position of the adapter. Make sure to point everything the right way.>
One downside of using adapters is that the bypass capacitors are
farther away from the chip. If that turns out to be a problem you can> try putting an SMD bypass cap on the adapter board.

If you get desperate, the NTE7164 is an SA602-compatible part. But you> won't enjoy the price tag.

Although MSOP adapters also exist, don't try to use one with an
Si5351A. That chip is fussy about the lead lengths of its bypass
capacitor and crystal. A much better idea is to use an Si5351A
breakout board; they are available from Adafruit, QRP Labs, and
Etherkit.

It appears that some opportunists are selling counterfeit parts. Be
wary of SA602 and SA612 DIPs (or the older NE602 and NE612 if anybody> offers those) from eBay and Ali Express.
On Mon, Sep 24, 2018 at 1:03 AM Michael <pixelwaster@gmail.com> wrote:>>
Arrow.com has smd SA612 for $1.66 each. Minimum of 1 ordered
with free>> overnight shipping. They do ship overnight on a few parts! The next
break points are at 10/1.4988, 100/1.3005, 1000/1.008
The date code is 1708 from Thailand and they have 1900 in stock.
If you are willing to wait three day you can get the parts form the
Netherlands dated 1827. Still free shipping.

Michael
N9XYP

On 9/23/2018 10:17 PM, na5n_qrp wrote:

Kits and Parts (Diz) also has the thru-hole versions shown on his
website ... the NE602AN and NE612AN, as well as the SA602AD
SMT part.>>> 5 for $10, or $2 each. Mouser also has the SMD versions for $2.88/1>>> and $2.45/10 with 11,000 in stock. DigiKey has them as well
for $2.36>>> each with 1,000 in stock. Search for SA602 or SA612 ... NE602/612
produces no results and seldom shown in their catalogs, but
they have>>> them. They're not as rare as some have claimed.




Re: SA612AN - really hot when VCC is applied

Mvs Sarma <mvssarma@...>
 

I think it is 2.45 each at 10 lot and NOT a lot total price.



On Mon, Sep 24, 2018 at 2:13 PM Shirley Dulcey KE1L <mark@buttery.org>
wrote:

I don't think anybody has said that the surface mount SA602 and SA612
parts are scarce. They're still in production and readily available
from distributors.

What is getting scarce is the through-hole version. NXP (successor to
Signetics and Philips) stopped making them a while ago and supplies
are drying up. Diz still has them for now, as does the Switch and
Parts Store (WB9KZY). The Elecraft KX1 switched to using an SMD mixer
and an adapter board before it went out of production, and I suspect
the K2 has done that as well. Generic 8-SOIC to 8-PDIP adapter boards
are available from many sources. One example is the SparkFun
BOB-13655, which is $2.95 for a board that's actually four break-apart
adapters. Another example is the Adafruit 1212: $2.95 for a six pack
of boards. You also need headers; the inexpensive snap-apart ones will
work just fine. I have also seen adapters from Schmartboard and
generic ones for sale at hamfests.

The chip on many of the 8-SOIC adapters is rotated 90 degrees from the
position of the adapter. Make sure to point everything the right way.

One downside of using adapters is that the bypass capacitors are
farther away from the chip. If that turns out to be a problem you can
try putting an SMD bypass cap on the adapter board.

If you get desperate, the NTE7164 is an SA602-compatible part. But you
won't enjoy the price tag.

Although MSOP adapters also exist, don't try to use one with an
Si5351A. That chip is fussy about the lead lengths of its bypass
capacitor and crystal. A much better idea is to use an Si5351A
breakout board; they are available from Adafruit, QRP Labs, and
Etherkit.

It appears that some opportunists are selling counterfeit parts. Be
wary of SA602 and SA612 DIPs (or the older NE602 and NE612 if anybody
offers those) from eBay and Ali Express.
On Mon, Sep 24, 2018 at 1:03 AM Michael <pixelwaster@gmail.com> wrote:

Arrow.com has smd SA612 for $1.66 each. Minimum of 1 ordered with free
overnight shipping. They do ship overnight on a few parts! The next
break points are at 10/1.4988, 100/1.3005, 1000/1.008
The date code is 1708 from Thailand and they have 1900 in stock.
If you are willing to wait three day you can get the parts form the
Netherlands dated 1827. Still free shipping.

Michael
N9XYP

On 9/23/2018 10:17 PM, na5n_qrp wrote:

Kits and Parts (Diz) also has the thru-hole versions shown on his
website ... the NE602AN and NE612AN, as well as the SA602AD SMT part.
5 for $10, or $2 each. Mouser also has the SMD versions for $2.88/1
and $2.45/10 with 11,000 in stock. DigiKey has them as well for $2.36
each with 1,000 in stock. Search for SA602 or SA612 ... NE602/612
produces no results and seldom shown in their catalogs, but they have
them. They're not as rare as some have claimed.





Re: SA612AN - really hot when VCC is applied

Shirley Dulcey KE1L
 

I don't think anybody has said that the surface mount SA602 and SA612
parts are scarce. They're still in production and readily available
from distributors.

What is getting scarce is the through-hole version. NXP (successor to
Signetics and Philips) stopped making them a while ago and supplies
are drying up. Diz still has them for now, as does the Switch and
Parts Store (WB9KZY). The Elecraft KX1 switched to using an SMD mixer
and an adapter board before it went out of production, and I suspect
the K2 has done that as well. Generic 8-SOIC to 8-PDIP adapter boards
are available from many sources. One example is the SparkFun
BOB-13655, which is $2.95 for a board that's actually four break-apart
adapters. Another example is the Adafruit 1212: $2.95 for a six pack
of boards. You also need headers; the inexpensive snap-apart ones will
work just fine. I have also seen adapters from Schmartboard and
generic ones for sale at hamfests.

The chip on many of the 8-SOIC adapters is rotated 90 degrees from the
position of the adapter. Make sure to point everything the right way.

One downside of using adapters is that the bypass capacitors are
farther away from the chip. If that turns out to be a problem you can
try putting an SMD bypass cap on the adapter board.

If you get desperate, the NTE7164 is an SA602-compatible part. But you
won't enjoy the price tag.

Although MSOP adapters also exist, don't try to use one with an
Si5351A. That chip is fussy about the lead lengths of its bypass
capacitor and crystal. A much better idea is to use an Si5351A
breakout board; they are available from Adafruit, QRP Labs, and
Etherkit.

It appears that some opportunists are selling counterfeit parts. Be
wary of SA602 and SA612 DIPs (or the older NE602 and NE612 if anybody
offers those) from eBay and Ali Express.

On Mon, Sep 24, 2018 at 1:03 AM Michael <pixelwaster@gmail.com> wrote:

Arrow.com has smd SA612 for $1.66 each. Minimum of 1 ordered with free
overnight shipping. They do ship overnight on a few parts! The next
break points are at 10/1.4988, 100/1.3005, 1000/1.008
The date code is 1708 from Thailand and they have 1900 in stock.
If you are willing to wait three day you can get the parts form the
Netherlands dated 1827. Still free shipping.

Michael
N9XYP

On 9/23/2018 10:17 PM, na5n_qrp wrote:

Kits and Parts (Diz) also has the thru-hole versions shown on his
website ... the NE602AN and NE612AN, as well as the SA602AD SMT part.
5 for $10, or $2 each. Mouser also has the SMD versions for $2.88/1
and $2.45/10 with 11,000 in stock. DigiKey has them as well for $2.36
each with 1,000 in stock. Search for SA602 or SA612 ... NE602/612
produces no results and seldom shown in their catalogs, but they have
them. They're not as rare as some have claimed.



Re: SA612AN - really hot when VCC is applied

Michael
 

Arrow.com has smd SA612 for $1.66 each. Minimum of 1 ordered with free overnight shipping. They do ship overnight on a few parts! The next break points are at 10/1.4988, 100/1.3005, 1000/1.008
The date code is 1708 from Thailand and they have 1900 in stock.
If you are willing to wait three day you can get the parts form the Netherlands dated 1827. Still free shipping.

Michael
N9XYP

On 9/23/2018 10:17 PM, na5n_qrp wrote:

Kits and Parts (Diz) also has the thru-hole versions shown on his website ... the NE602AN and NE612AN, as well as the SA602AD SMT part.  5 for $10, or $2 each.  Mouser also has the SMD versions for $2.88/1 and $2.45/10 with 11,000 in stock.  DigiKey has them as well for $2.36 each with 1,000 in stock.  Search for SA602 or SA612 ... NE602/612 produces no results and seldom shown in their catalogs, but they have them.  They're not as rare as some have claimed.


Re: SA612AN - really hot when VCC is applied

Paul NA5N
 

Richard Seguin writes:

I noticed this evening that www.kitsandparts.com sells some of those SMD
mixers.
Kits and Parts (Diz) also has the thru-hole versions shown on his website ... the NE602AN and NE612AN, as well as the SA602AD SMT part. 5 for $10, or $2 each. Mouser also has the SMD versions for $2.88/1 and $2.45/10 with 11,000 in stock. DigiKey has them as well for $2.36 each with 1,000 in stock. Search for SA602 or SA612 ... NE602/612 produces no results and seldom shown in their catalogs, but they have them. They're not as rare as some have claimed.

I mount my surface mount NE602s or other SMD ICs on a homebrew Manhattan style adapter. Basically a small square of copper clad and cut the traces for the pins with a dremel tool and thin cutting wheel. Just 3 cuts for the 4 pins on each side, then cut those in two vertically to make the 8 pins. I trim them so the pins stick out 1/8 to 1/4 inch for soldering the connections and external components. Works great and cheap. A steady hand comes in handy!

Hard to complain over the $2-3 cost. You're buying a lot of proven functionality for a couple of bucks with the good ole 602 chip. Biggest problem is they have a low P1dB so can be easily overloaded when used as the front end RF mixer. However, I have never noticed that unless operating in close proximity to others, like Field Day. On the other hand, a few external components and you have a nice product detector with a BFO.

72, Paul NA5N

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