UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > Other Discussions > Homebrew Equipment

Notices

Homebrew Equipment A place to show, design and discuss the weird and wonderful electronic creations from the hands of individual members.

Reply
 
Thread Tools
Old 13th Aug 2019, 7:04 pm   #161
julie_m
Dekatron
 
Join Date: May 2008
Location: Derby, UK.
Posts: 7,306
Default Re: More Chinese AM radio kits

What do you expect when you go borrowing words from other languages willy-nilly? Just as English has different names for an animal when it's alive in a field and dead on your plate, so it has picked up different words for "bonding metals using a molten metal filler" depending on the particular subdomain of engineering. "Welding" and "Soldering" are the same word in many languages.
__________________
If I have seen further than others, it is because I was standing on a pile of failed experiments.
julie_m is offline   Reply With Quote
Old 13th Aug 2019, 10:57 pm   #162
Herald1360
Dekatron
 
Herald1360's Avatar
 
Join Date: Feb 2007
Location: Leominster, Herefordshire, UK.
Posts: 13,340
Default Re: More Chinese AM radio kits

Useful, but only if you already know what a superhet is and how it does it!
__________________
....__________
....|____||__|__\_____
.=.| _---\__|__|_---_|.
.........O..Chris....O
Herald1360 is online now   Reply With Quote
Old 14th Aug 2019, 9:50 am   #163
boxdoctor
Heptode
 
boxdoctor's Avatar
 
Join Date: Sep 2010
Location: Ripley, Derbyshire, UK.
Posts: 681
Default Re: More Chinese AM radio kits

Thanks, Avid Nerdlinger for your handy tip. As it happens, The P.C.B. is marked with the component values, and the Chinglish assembly instructions given in the original ad on Ebay (but, sadly, not with the kit) give the colour/function of the I.F.T.s and transistors, so I should be well away with those clues.

Herald 1360, what you say is very true. I think, given the available instructions, a beginner would be very lucky to successfully build this kit without some help from a knowlegeable person.
Fortunately, this project is only being done out of of academic curiosity. Tony.
__________________
The job "couldn't be done".
He didn't know that,
So he did it.
boxdoctor is offline   Reply With Quote
Old 14th Aug 2019, 10:17 am   #164
MrBungle
Dekatron
 
MrBungle's Avatar
 
Join Date: Jun 2016
Location: London, UK.
Posts: 3,322
Default Re: More Chinese AM radio kits

I’m not exactly a beginner (just built a working superhet from scratch and a K2) and I’ve built two of these Chinese radios and neither of them worked properly so you’re right

I was hoping to modify one a little bit and try and add a BFO.

On the IFTs I found a chart of Chinese symbols for colours on the web and used that. Appears the RF side of mine both worked but the audio didn’t.
MrBungle is online now   Reply With Quote
Old Yesterday, 3:23 pm   #165
boxdoctor
Heptode
 
boxdoctor's Avatar
 
Join Date: Sep 2010
Location: Ripley, Derbyshire, UK.
Posts: 681
Default Re: More Chinese AM radio kits

I put the kit together over the weekend, and it does not function. The problem is in the audio section (uses the one transformer (driver) configuration). Some real jobs have come in meanwhile, so it has had to be put on the Roundtuit shelf for a day or two.
Further investigations will be made shortly. All currents drawn are within the specified limits. Tony.
__________________
The job "couldn't be done".
He didn't know that,
So he did it.
boxdoctor is offline   Reply With Quote
Old Yesterday, 4:30 pm   #166
Tully Bascombe
Triode
 
Tully Bascombe's Avatar
 
Join Date: Mar 2019
Location: Chesterfield, Derbyshire, UK.
Posts: 24
Default Re: More Chinese AM radio kits

Have you bridged all the test point breaks on the PCB? Is the transformer the right way round?
Tully Bascombe is offline   Reply With Quote
Old Yesterday, 5:04 pm   #167
Top Cap
Octode
 
Top Cap's Avatar
 
Join Date: Mar 2006
Location: Watford, Hertfordshire, UK.
Posts: 1,192
Default Re: More Chinese AM radio kits

Quote:
Originally Posted by boxdoctor View Post
I put the kit together over the weekend, and it does not function. The problem is in the audio section (uses the one transformer (driver) configuration). Some real jobs have come in meanwhile, so it has had to be put on the Roundtuit shelf for a day or two.
Further investigations will be made shortly. All currents drawn are within the specified limits. Tony.
Had similar fault, radio works but weak audio. Scope shows only one output transistor working but non-working transistor is OK. Output from driver transformer does not look very good, definitely not equal and opposite . Suspect transformer so the whole thing will go into the junk box for when I need I.F. transformers etc.. No big deal, have plenty of LW/MW radios here, fun building apart from lousy circuit board with poor track adhesion.
__________________
Whether the Top Cap is Grid or Anode - touching it will give you a buzz either way!
Top Cap is offline   Reply With Quote
Reply

Thread Tools



All times are GMT +1. The time now is 10:53 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Copyright ©2002 - 2019, Paul Stenning.