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People need to try and work with SMD parts...it IS easier than you think. I also use the approach below, but use tweezers to hold the part in place while soldering. I find:


the the left-most pair above works best for hold the SMD in place while soldering. The set costs under $10 online.

Jack, W8TEE

SMD is easy.? So much better than through hole.
I put solder on one pad.? Drop the part, push it around with an exacto knife.
Hold down with a finger or (finger nail for small 0805 parts). Solder the one
pad, then the rest.? Solder braid if you get bridging.
73,
Gary
WB6OGD

Looks like a useful technique for SOIC parts, as shown in the picture.
There are many kits that use a few SMD ICs of that size along with
mostly through-hole components. The Softrock series is a good example.
I'm guessing that the picture comes from one of Diz's own kits.

Not as big a help for smaller form factors like TSSOP. They're so
small that they'd be hard to tape down, and the big problem you have
with those is solder bridges between the closely spaced leads. I've
never had much success dealing with TSSOP with a soldering iron and
wire solder; I'll always get out the heat gun and solder paste for
those. I know that some people have made it work by putting down a
bunch of solder and then using solder wick to remove most of it but I
haven't gotten that technique to work.

My first search of Mouser showed the 22MHz, 26MHz, and 29MHz not available.

Second try found them all.

Bob Macklin
Seattle, Wa.


---
New Outlook Express and Windows Live Mail replacement - get it here:

On 7/13/2019 7:19 PM, Jim Kortge wrote:

On 7/13/2019 3:10 PM, k6whp wrote:

John,

As I [perfunctorily] read the manual and schematic, the Sierra requires 7 matched 4.915 MHz crystals for the main board and 1 each of the following for the band modules:

RF Crystal PMO

3.500-3.650???? 11.500
7.000-7.150???? 15.000
10.000-10.150 18.000
14.000-14.150 22.000
18.000-18.150 26.000
21.000-21.150 29.000

All of the above crystals appear to be in stock at Mouser in HC49 /HC49U packages (large case) in the range of $0.44 to $0.79 in single quantity.? So the premix crystals are not an issue.

72,

Jim, K8IQY

An update to the above, the 22 MHz is in a HC-49US short case at $0.47 per unit and in stock.

Digikey might also have all of them in the larger case, but I haven't checked.

72/73,

Jim, K8IQY

Chuck,

The only way I know to beat USPS cost is to sign up with someone like Stamps.com for $17.99 per month. That will get you a 40% discount on Priority mail shipping. I think at one time you needed to ship 200 packages per month. But I believe that is no longer the case.

Ray,
AB7HE

On 7/13/2019 3:10 PM, k6whp wrote:

John,

As I [perfunctorily] read the manual and schematic, the Sierra requires 7 matched 4.915 MHz crystals for the main board and 1 each of the following for the band modules:

RF Crystal PMO

3.500-3.650 11.500
7.000-7.150 15.000
10.000-10.150 18.000
14.000-14.150 22.000
18.000-18.150 26.000
21.000-21.150 29.000

All of the above crystals appear to be in stock at Mouser in HC49 /HC49U packages (large case) in the range of $0.44 to $0.79 in single quantity.? So the premix crystals are not an issue.

72,

Jim, K8IQY

All we need is one more mode.? Sample for 1sec and display, via scrolling
or whatever, the results down to 1Hz.

I agree about the Guys dial kit.? I bought a number of them and use them.
They are small and easily fit in an enclosure.? I floor mount them,
that is use only the bottom two holes and use the Keystone right angle
brackets.? Requires some nylon spacers to keep nut/screw from shorting
things out due to close spacing and their use of 2-56 screws.

ciao, chuck, k7qo

that is one I did not find, here are a few others including DL4YHF web site:



direct link to source and precompiled firmware

variation using oscillator module rather than crystal clock

for another interesting variation

Can't beat the QrpGuys digital dial kit - lots of band for the buck.

cheers, Graham ve3gtc

Google translate may help.

I use it frequently on non-english web pages even to the point of being able read German, French, and Russian radio forums.

cheers, Graham ve3gtc

Mouser has all but the 22,26, and29
DigiKey has the 22 and 26.

John,

As I [perfunctorily] read the manual and schematic, the Sierra requires 7 matched 4.915 MHz crystals for the main board and 1 each of the following for the band modules:

RF Crystal PMO

3.500-3.650 11.500
7.000-7.150 15.000
10.000-10.150 18.000
14.000-14.150 22.000
18.000-18.150 26.000
21.000-21.150 29.000

Onesies-twosies might not be that expensive.
--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"

Consider using a DDS in their place

I'm looking at using a microcontroller for computer interface (CAT) and
replacing the VFO with a DDS.

I'm working on doing that to a NorCal40 right now.


Bob Macklin
K5MYJ
Seattle, Wa.
"Real Radios Glow In The Dark"

One thing to consider if one is to build the band modules is that some of
the crystals at the needed frequencies will be tough and or expensive to
get.

73 - john - n0hj

Sehr gut in den Sierra Boards, mein Freund. Aber die bestellseite ist auf deutsch und was von uns die nicht "habla" machen? Wie bestellen wir?

(Very good on the Sierra boards, my friend. But the order page is in German and what of us who do not "habla"? How do we order?)

--
William, K6WHP
"Cheer up, things could get worse..so I cheered up and, sure enough, things got worse!"

On 7/13/19 12:43 PM, Nick Kennedy wrote:

I haven't looked at how it affects "pullability" of the crystals in a VXO
though.

My 2 cents worth on "pullability" of crystals...

My experience is that full size 49 xtals offer a larger freq span than the short stuff.

Another thing...Over many years, I have seen multiple xtals in parallel to increase freq span.

I discovered that placing a small value cap (range 4p7 +/-) at the junction of xtals/series inductor to ground does the same thing.

At least it seems that way. Check out Cx on the left side of this schematic:

73, Diz, W8DIZ

A discussion on the differences came up somewhere not long ago. I had made
some measurements while re-doing the filter in my ATS-3 and also when using
the "short" crystals in another ("measurement receiver") project.

They (the short crystals) showed good Q in comparison with the HC-49/U
crystals and I didn't pay much attention to the relative Lm and Cm values
until I found some info from Wes Hayward saying that the reactances are
much larger in the short crystals.

Well yes, it was as plain as it could be that the short crystals had Lm
values three times as high as for standard height crystals on the same
frequency. Hayward said that the differences could make filter design with
these crystals more challenging.

I haven't looked at how it affects "pullability" of the crystals in a VXO
though.

73-

Nick, WA5BDU

I stand corrected.? I did a quick search and found that the DL4YHF frequency counter
code is open source.



So after the IF NC40A experiments I can go off and do a fixture for crystal matching
that may (note the word 'may') be easier to use.

Yet another rabbit hole.? Love the movie 'Holes'.

chuck, k7qo, in the desert digging holes

Project is progressing, but I hit a bump in the road or I ran over
something.? :-)

First.? Because I wanted to try the higher frequency LO experiment
for the NC40A for changing IF to 9MHz and for other bands I wanted
to build up several rigs.? Easy.? Got the boards.? Got the parts.
Don't have the time.? You know the drill.

****
I do want to give away as many 4.096MHz crystals as possible.? I still have not seen
one person in this group come forward with how to beat the USPS
system.? Otherwise it is better for you to order 50 crystals off of
aliexpress.com and do you work and do it cheaper than the cost for
me to mail you a small matched set.? Life in the 21st century hasn't
gotten any easier.
****

You guys know about the QRPGuys.com digital display for $20 for either
PTH or SMD versions.? It is based on the work of DL4YHF and can be
found on the web in various places.? Doug and Ken got permission to
use the work for the digital display.? The Chinese use the same code in
the red PCB Chinese Crystal Checker and Frequency Counter, which this
group discussed a few years back.? The code is not open source.

Last night, for the 4.096MHz crystals, I got to the IF crystal filter
and needed to match the crystals.? Instead of taking time to setup
a matching system I did the following quick and dirty setup.? This
is based on a technique that is mentioned in the digital display
manual for the Guys.? If you subtract a different value from you
input RF frequency being read, you can gain some more digits.

You want to match crystals to 10-20Hz?? You need another RF source
or a crystal of the right value.? I'm matching 4.096MHz and I want to
remove the leading 4 from the display.? Easy.? I take a 4.000MHz crystal
and read its value in the crystal checker and store it in memory to be
subtracted from the crystals being checked thereafter.? Attached is
a photo (blurry) of the result for one of the crystals.? I turned off
the white LED lighting to get the desk dark enough to read and photograph
the display, but the exposure time went up and I moved the camera.? Should
have used a tripod or I have a clamp, but didn't think of it.? But you
get the picture.? ;-)

The display is showing 95.968KHz.? We know that it's KHz because the decimal point
between the 5 and 9 digits is blinking.? This means the display is reading
down to 1Hz!!? So, I quickly matched 4 crystals to within 5Hz. Because
I did not have to keep a record, I just took a pile of crystals and put
4 that read the same value into the IF of the NC40A.? It goes faster than
the time it takes to write it up.? I didn't need to kill a tree writing
down values for each crystal measured, sorting and pull the ones to be used.

So the difference between 4.000MHz (not really, but it works as I don't
need to know the value exactly) and the 4.096MHz crystal in the checker
is 95 968Hz (95,968Hz, but in some countries that is 95.968Hz, and now
we are all confused).? Get 3 more with the same value or very close and
the crystals are matched well enough for this project.

Eons ago I thought of the same procedure, but using the crystal with
the lowest reading in a batch and store its value and subtract. But,
the code will not do it and since it is not open source we can not fix
it.? Some one do an open source counter and let us all use it in a
matching system and I'll do the PCB.? Homework for you guys.

The bump:? Had to recalculate some L values for tuned transformers, like
T3.? Thanks Diz for his online calculator.? Here is how I use this valuable
resource.? Go to the FT37-61 toroid and you get a calculator. Feed it the
23T and 47pF value.? Hit Calc.? You get 4.302MHz as the tuned frequency.
Clear the calculator and put in 4.915MHz in the freq box and put 47 in
the cap box and you get 20T.? If you do 4.915MHz and 23T and calculate
you get 36pF.? The original kit had 39pF, which is much closer than the
current.? Some one can experiment for me, please.? You can see why I wind
up in so many rabbit holes.

The point.? Even if you buy a kit, you need to do some checking for some
improvements that you might find yourself.? I suspect that the value was
changed due to availability of parts and costs.? The reason will never be
known as the players are off doing other things or retired from the kit
business.

The other bump.? I have to sacrifice another NorCal40A and remove the
LM393 for this project and I have to find the poly caps for the VFO
to insure we are all on the same page in doing the drift tests. So
we'll be back sometime later with the latest news.? I don't seem to
have either C0G or NP0 values to use in place of.

Sorry for the delay.? Techies are working to bring the project back online.

FYI

chuck, k7qo, 'I may be slow but I'm ahead of you.'