Re: SX-100 Repair Problems - Bumblebees!
Keith, the problem with old “bumble bees” is that he color bands color also change with time. ? Best I can see is : ? Bee1: the left one seems to be red, violet, yellow, white, blue = 2, 7, 0000, 9, 6 = 270000 pF = 0,27?F, 10%, 600V Bee1: right one: red, red, yellow, white, blue = 2, 2, 0000, 9, 6 = 220000 pF = 0,22?F, 10%, 600V Bee2: red, red, yellow, gray, red = 2, 2, 0000, 8, 2 = 220000 pF = 0,22?F, 10%, 200V Bee3: brown, gray, red, gray, blue = 1, 8, 00, 8, 6, = 1800pF = 0,0018?F, 10%, 600V Bee4: brown, gray, red, gray, blue = 1, 8, 00, 8, 6 = 1800?F = 0,0018?F, 10%, 600V ? On some bumble bees, the use of 8 or 9 on the tolerance band really means 10% practically. These ones can be measured on an impedance bridge at 1kHz, but… The values they measure now does not necessary reflects the original manufactured values. The dielectric (oil impregnated paper) do not have the same dielectric constant since it had been contaminated with ambient oxygen. ? Values out of the “standard” 10% decade values makes no sense, so… ? 73, Jacques, VE2JFE in Montreal
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Re: SX-100 Repair Problems - Bumblebees!
Thank you Dan. I was on the right track. You are correct on having problems with the colors. I have found a good chart for reference now also is helping. Thankfully there are not a lot of these in this radio. ? ? ?
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From: [email protected] <[email protected]> On Behalf Of Dan
Sent: Friday, March 22, 2024 8:06 PM
To: [email protected]
Subject: Re: [HallicraftersRadios] SX-100 Repair Problems - Bumblebees!? ?The first three color bands determine the value. Start with the color band nearest an end. The color coding is the same as the traditional three color resistor code. In your first example below it’s red, red, orange or 22 times an orange multiplier of 1000 for 22,000 pF or .0022 uF. .002 is a commonly found film cap today. Sprague Bumblebee color code values are always in pf. To convert to uF, divide by 1,000,000.? In your second photo we see red, red, yellow. That’s 22 x 10000 = 220,000 pF/1,000,000 or .22 uF. Summarizing, use the typical three color resistor code. First two colors are a value, the third is the multiplier, the result is always in pF and divide by 1,000,000 to get uF. It’s pretty common to have difficulty discerning some colors after ~50-70 years, especially violet, gray, brown, etc. If in doubt, locate the cap on the schematic and see what the value is declared to be. You can almost always figure it out or confirm an uncertain color and value. ?
On Mar 22, 2024, at 7:31?PM, Keith <kd4avp@...> wrote:
?Ok gentlemen.....Need help here before I make a mistake. Couple of the bees have me confused on values.?
Can I get a second opinion please?
Thanks
Keith
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Re: SX-100 Repair Problems - Bumblebees!
?The first three color bands determine the value. Start with the color band nearest an end. The color coding is the same as the traditional three color resistor code.
In your first example below it’s red, red, orange or 22 times an orange multiplier of 1000 for 22,000 pF or .0022 uF. .002 is a commonly found film cap today.
Sprague Bumblebee color code values are always in pf. To convert to uF, divide by 1,000,000.?
In your second photo we see red, red, yellow. That’s 22 x 10000 = 220,000 pF/1,000,000 or .22 uF.
Summarizing, use the typical three color resistor code. First two colors are a value, the third is the multiplier, the result is always in pF and divide by 1,000,000 to get uF.
It’s pretty common to have difficulty discerning some colors after ~50-70 years, especially violet, gray, brown, etc. If in doubt, locate the cap on the schematic and see what the value is declared to be. You can almost always figure it out or confirm an uncertain color and value.
Dan WB4GRA
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On Mar 22, 2024, at 7:31?PM, Keith <kd4avp@...> wrote:
?Ok gentlemen.....Need help here before I make a mistake. Couple of the bees have me confused on values.? Can I get a second opinion please? Thanks Keith
<Bee1.jpg> <Bee2.jpg> <Bee3.jpg> <Bee4.jpg>
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Re: SX-100 Repair Problems - Bumblebees!
Ok gentlemen.....Need help here before I make a mistake. Couple of the bees have me confused on values.?
Can I get a second opinion please?
Thanks
Keith
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Re: Thinking about an SX-117
Don, I like your summary below. I agree with every part of it.
I restore gear because I like to and usually learn something from
each piece. Keeps my brain alive.
This may be a commercial enterprise for some of us but its not for
me. I did make my living out of electronic servicing for many years but
now do it has a hobby. Determining value is a matter of what I get out
of it, not what I am able to sell something for.
You have said it very well, thank you.
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On 3/22/2024 12:58 PM, don Root wrote: Bob, Justin and all
Seems to me there is room for all ideas.
Some people like a challenge, and some don’t .
Some people like to gamble, and some don’t .
Some people like to ?bring things back from the dead, and some don’t.
Some people ?won’t be happy without a “mint” rig, and some don’t mind
one that has had a life.
Then there are modifications beyond those instigated by the factory.
And there is also the idea of having and keeping everything as authentic
as possible.
And is it going to be in day to day use, or is it another anchor that I
need to possess ?
Any parts cost money, and labor costs of installing new solder is a
whole other topic.
And besides, no matter what you spend, it is a cheaper life than going
to the beer hall.
--
Richard Knoppow
Los Angeles
WB6KBL
SKCC 19998
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Re: Thinking about an SX-117
On Fri, Mar 22, 2024 at 02:46 PM, Justin Bowser - KI5GKD wrote:
Floyd - Thanks for the review.? Seems like the receiver has several drawbacks with few up-sides to offset them.
Well, I wouldn't go that far.? When you look at the competition from that period and in this new price range, I'd rate the SX-117 pretty high.? Other receivers from that period, such as the Hammarlund HQ-170A, suffer from temperature stability problems since it doesn't have a crystal controlled first conversion oscillator.? I think that Drake got most things right in that time frame.? If you don't intend to use the SX-117 on CW, then the AVC shortcomings won't enter into it at all.? The BFO adjustment I mentioned isn't a factor either for just SSB use.? You set it one time and that's it.? It's really quite a good receiver for SSB.?But, whatever you decide to buy, I'd advise avoiding anything that has spent several years of its life sitting on the garage or basement floor, subject to high humidity, temperature extremes, vermin and dirt.? Unfortunately, sellers ask about the same prices for such a beast as one that was pampered all its life. 73, K8AC
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Good question.? I'll have to scope that out and report back.? What I can't tell from the documentation is whether it inserts the leading PTT for code sent from the keying lever or if the PTT lead time is inserted only for code sent from the PC.? You can also specify a trailing time that controls how long the PTT stays up after the last code element is sent.?
Floyd
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Re: SX-100 restore project
Hi Scott, ? Yes: a work of love. For the SX-42, despite that it can be done, it will depend on which version…. ? 73, Jacques, VE2JFE in Montreal
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Re: SX-100 restore project
That is such an awesome schematic! I wish there was one for the SX-42! it would make things much easier to follow!
Thanks for doing it!
I saved it in case I ever am able to get a SX100.
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Can I include attachments on this?listserv?? Trying now...Let's see if the pdf goes through...
On Wed, Mar 20, 2024 at 7:45?AM Keith < kd4avp@...> wrote:
Little more clean up on the internals this evening.? Decided against the “bath” approach when a good spray down with CRC gave these results. Lubed the appropriate parts. Dials turn really smooth. Overall pleased with results so far. Awaiting
the cap can and repair resistors.?
See no point going further till those get here. I did snag a 100hz crystal today just in case. I am worried this one may be damaged.?
?
Just in case you do not have a good copy of the operation and service manual.
Walt Cates, WD0GOF
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A majority of acceptance is not proof of correctness.
And I forgot to add, thank you so much for including that great schematic pdf file. This will be a great help.
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Re: Thinking about an SX-117
Bob, Justin and all Seems to me there is room for all ideas. Some people like a challenge, and some don’t . Some people like to gamble, and some don’t . Some people like to ?bring things back from the dead, and some don’t. ?? Some people ?won’t be happy without a “mint” rig, and some don’t mind one that has had a life. Then there are modifications beyond those instigated by the factory. And there is also the idea of having and keeping everything as authentic as possible. And is it going to be in day to day use, or is it another anchor that I need to possess ? ? Any parts cost money, and labor costs of installing new solder is a whole other topic. And besides, no matter what you spend, it is a cheaper life than going to the beer hall. ? ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Robert Needleman via groups.io
Sent: Friday, March 22, 2024 2:59 PM
To: [email protected]; [email protected]
Subject: Re: [HallicraftersRadios] Thinking about an SX-117? Justin - I agree with Walt's price range because the more you spend on a vintage radio of any brand, the more likely it is that it will be? in fully working condition, and not need replacement parts, especially vacuum tubes, which have become extremely expensive since most are no longer made, at least not in the US. So buying a 'bargain' radio may wind up costing you almost as much as the radio is worth if you have to replace several bad tubes or other expensive components. I recommend only buying vintage tube gear in person where you are able to verify that it is working properly, or have some type of video verification of it's performance. IF not, then consider it as being 'for parts or repair' only.? I understand you always try to find 'bargains' but when it comes to vintage tube gear, that 'bargain' may turn out to be no bargain and wide up being a real 'bite in the wallet' if you have to re-tube it, or have to replace other expensive components to get it working properly.
In a message dated 3/22/2024 2:46:59 PM Eastern Daylight Time, justin.bowser@... writes:
Walt - Thanks for the price range.
Floyd - Thanks for the review.? Seems like the receiver has several drawbacks with few up-sides to offset them.
To all who have offered up some for sale, thanks but right now I'm just looking and normally don't buy anything unless it's a bargain!
73,
--
Justin B.
KI5GKD
-- don??? va3drl
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Re: Thinking about an SX-117
I'm well aware of the possible pitfalls of buying stuff I can't put hands on first.? I've only been bitten really bad once and that was on a Swan 250 which somebody stuffed it full of bad tubes and flogged it on FleaBay!? After filling it up with good tubes it turned out to have a really strange problem that took much help and 6 months of head scratching!
I always factor in the cost of re-capping and a few tubes and minor problems help keep the mind sharpened and me out of mischief!
73,
--
Justin B.
KI5GKD
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Re: Thinking about an SX-117
I agree with you Robert. Sometimes these radios can be like going down the literal rabbit hole. I get very skeptical of ebay sales. You truly have no idea what you will end up with. I have bought a few off ebay....but I made sure to know exactly what I was getting. Many times after I get answers to my questions, they are usually quite ready to lower the price when accepting offers. Then sometimes they have lost their proverbial mind and think its worth its weight in gold even though rust is showing on 75% of the item.?
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Re: Thinking about an SX-117
Justin - I agree with Walt's price range because the more you spend on a vintage radio of any brand, the more likely it is that it will be? in fully working condition, and not need replacement parts, especially vacuum tubes, which have become extremely expensive since most are no longer made, at least not in the US. So buying a 'bargain' radio may wind up costing you almost as much as the radio is worth if you have to replace several bad tubes or other expensive components. I recommend only buying vintage tube gear in person where you are able to verify that it is working properly, or have some type of video verification of it's performance. IF not, then consider it as being 'for parts or repair' only.? I understand you always try to find 'bargains' but when it comes to vintage tube gear, that 'bargain' may turn out to be no bargain and wide up being a real 'bite in the wallet' if you have to re-tube it, or have to replace other expensive components to get it working properly.
?
73,
Bob K3AC
In a message dated 3/22/2024 2:46:59 PM Eastern Daylight Time, justin.bowser@... writes:
?
Walt - Thanks for the price range.
Floyd - Thanks for the review.? Seems like the receiver has several drawbacks with few up-sides to offset them.
To all who have offered up some for sale, thanks but right now I'm just looking and normally don't buy anything unless it's a bargain!
73,
--
Justin B.
KI5GKD
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Re: Thinking about an SX-117
Walt - Thanks for the price range.
Floyd - Thanks for the review.? Seems like the receiver has several drawbacks with few up-sides to offset them.
To all who have offered up some for sale, thanks but right now I'm just looking and normally don't buy anything unless it's a bargain!
73,
--
Justin B.
KI5GKD
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Hi Floyd,
Wow, I hadn't known about this Winkeyer feature!? I'm curious about how it handles the initial delay.? I scanned the manual and couldn't find the answer.? Are all the dits and dahs delayed by the lead time between paddle contact closure and output?? Or does only the first element since the PTT output last? dropped have a delayed start?? I think it'd be difficult to use if everything sends out 30-40 ms after my fingers feel the mechanical contact at the paddle.
Cheers,
Halden VE7UTS
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HT-32B; more transformer questions...
Hello,
I am now working on a HT-32B that I obtained several years ago that had been in someone's garage/shed and was in rather poor shape. (The dial had pretty much flaked off due to water damage, I believe.) ? I thought about using it as a parts unit, but had second thoughts and have begun to dig into it.? (Actually, I had started that process a few years back but, at the time, when I started to power it up via a VARIAC, the fuse blew; I'd assumed it was the transformer, so then just put the whole thing aside, until now.)
Question 1: This unit had apparently been worked on by a previous owner.? The rectifier tubes have been replaced by silicon diodes.? Also, the transformer appears to have been replaced.? (The primary and secondary wires are connected to the original wiring via wire nuts.)? The curious thing is that the transformer has the number 052-000877; according to information posted on this site, I think by Walt, the transformer number used in the HT-32B was a 052-400877.? The other odd thing about this particular transformer is that, although it has the 70A tap on the primary (for a fan), it does NOT appear to have the 5VAC yellow and brown filament wires in the secondary; (if they were present, but later were cut off, I certainly can see no wire stubs down inside the housing of the transformer.)?? Just wondering about the -000877 ID of this transformer and whether it was a type that did not have the 5VAC filament windings?
Question 2: I previously mentioned that I'd assumed that this transformer had windings shorted.? In order to check this, I'm assuming I can check the resistances per the Voltage and Resistance Chart. Am I correct??? [Keep in mind that this one has no 5VAC filament wires present, or if they're there, they're not accessible to me.]
Thanks for your comments and advice!
Jim
KD0WF
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Re: Thinking about an SX-117
I plan to bring 3 to Dayton.?
Contact me off-list for more info if you are interested. At least 2 HT-44 / PS's also.?
Thanks?
Jeff
W8KZW
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Interesting stuff, Halden.? I'd say my HT-44 is performing like yours with the timings.? At around 30 wpm, my initial dit is practically missing.? I haven't scoped any of this yet, but the initial dit is observed as just a low power spike in the output.? My HT-44 has the optional T/R relay installed and I assumed that the pick time of that relay was primarily responsible for the problem, but apparently that isn't true.? I was going to disable that relay and use a Johnson TR switch for antenna switching to see if that made any difference.? I'll get into all that as soon as I wrap up the audio and VOX problems.? The keying waveforms look good and that last photo with the hump at the initial peak may or not cause a click to be heard.? I'm still thinking there might be a way to trigger the start of the transmit process with an external closure of the PTT line prior to the first code element being sent.? My Winkeyer USB has the ability to output a PTT closure that leads the first code element by a user specified time.??
Floyd
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Re: Thinking about an SX-117
Having just restored an SX-117, I'll give you my opinions which I'm sure others will strongly disagree with.? My SX-117 came to me in cherry condition, no dirt, no marks, not even any dust inside.? Looked new and I paid the price for that.? Of course, it didn't work.? All the tubes were original Hallicrafters brand and that led me to think it had never been serviced.? After replacing three bad tubes, I bit the bullet and bought a complete new set.? Whether or not the receiver is a can of worms depends upon the test equipment you have and your level of technical expertise.? The physical design of the receiver is a bit misleading - it doesn't look 62 years old, but design-wise it certainly is.? The first thing I discovered is that there was no stock crystal for the 28.0 to 28.5 MHz portion of 10 meters, only 28.5 to 29.0 is covered.? That's where most of the 10 meter activity was at the time.? The designers weren't targeting CW operation - there's no CW position on the function switch (you use one of the SSB positions).? The BFO frequency isn't fixed for LSB and USB.? You have to play around with the BFO tuning and switching back and forth between LSB and USB to get it adjusted right.? Then you have to be happy with the result for CW or you'll have to go through the process again next time you're listening to SSB.? The AVC has one decay speed and that was changed over the production versions.? The earlier version is a good compromise between SSB and CW.? There's no provision for turning off the AVC.? There's no noise blanker, but there is a noise limiter which I find to be useless on any noise I've encountered so far.
On the plus side, my unit is very stable and there's no noticeable drift.? The tuning mechanism is a pinch drive and it's very smooth with no backlash and the tuning rate is slow enough for SSB and CW.? There are no dial strings to deal with.?
It's relatively easy to work on as the top and bottom panels can be removed to get at the top and bottom of the chassis without taking the receiver out of the cabinet.? The selectivity is adequate but not quite as good as a receiver that uses filters.? The AM selectivity is 5 kHz, which is a bit narrow if you intend to use it for AM operation.??
73, Floyd - K8AC
??
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On Thu, Mar 21, 2024 at 05:16 PM, waltcates wrote:
OK, now, do you have an SX-117 to mate it with??
?
Yep - I restored the SX-117 first and it's working well.??
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Jacques_VE2JFE
Floyd - K8AC
don Root