GRUNDIG CONCERT BOY 1100

I recently took a chance and won this radio at an auction; untested, with a seized tuning mechanism and coated with nictone.

When I got it on the bench, of course, it was totally non-functional. A little probing revealed a shorted filter capacitor in the power supply, which prevented it from working from either AC or batteries. A higher voltage and capacitance-rated part fixed that.


As for the seized tuner, I didn't have a clue what was going on. Thanks to the Internet and Google, I found that this was a common problem on Grundigs of this vintage ('73-'78). Apparently, the grease in the tuning capacitor hardens over time. One suggestion, which worked well for me, was to gently heat the capacitor with a hair dryer until the grease melted, then wash it away with a solvent like lighter fluid. I then re-greased the gears and pivot points with lithium grease, being careful not to get it on the plates. Result.

An unknown knucklehead who owned it before me decided that the headphone jack on the back (which works perfectly well) was not good enough for him. So, he proceeded to drill a hole in the front of the unit, just above the "G" in Grundig, and mount his own jack. The jack's now gone, but the hole remains. As for the nicotine...well, it's gone too, thanks to Windex and paper towels.

Concert Boy Goliath (left) and Partner David (right)

Since I've had my Telefunken Partner 500 for many years and am familiar with its characteristics the most, I will again use it as a benchmark. It seems like an unfair comparison when you look at the relative sizes of these radios...like David versus Goliath. But David puts up a good fight.

Right away, not surprisingly, the difference in bass presence goes to the Grundig. While the Partner's bass response for its size is excellent, physics says the bigger box is going to win. This Grundig big boy comes in at a whopping footprint of 41cm x 22cm x 10cm (approx.) [about 16.25" x 9" x 4"].

The Grundig's communications receiver - style tuning knob 

With telescopic antennas on both radios retracted, it was evident that the FM sensitivity of the Concert Boy was also better than the Partner's. In an urban area, the Partner gets overloaded easily, so lowering the antenna is required to prevent "ghosting" and distortion. The Grundig handled this proliferation of FM signals better, even with its antenna fully extended. Another point for Goliath, but his luck is about to run out.

Switching to the shortwave bands, the Concert Boy was almost useless on its K2 band (SW2 - 6.1 to 18 MHz) because of extreme feedthrough of local FM signals clobbering the weak shortwave signals. While the Partner had no such issue on the 19 m band through to the 41 m band, when a shortwave signal was heard on the Grundig between the FM splatter, the Grundig was slightly more sensitive.

That gap was closed at the 49 m band, where the sensitivity of both radios seemed comparable (on a subjective basis - not measured), and the FM interference on the Grundig subsided somewhat. One advantage the Concert Boy has is a second band (K1 or SW1), which is a bandspread band for 49 m (5.9 -6.23 MHz). While this makes tuning easier, I still find the tuning mechanism somewhat stiff, yet springy and imprecise. More heat and grease needed, perhaps?

Testing longwave here in North America is pointless, so I'll discuss AM performance. The same FM feedthrough problem exists on the Grundig if, for some reason, you leave the telescopic antenna extended. Since the AM band uses the internal loopstick antenna, keep the antenna down when listening to this band. Otherwise, the Concert Boy once again becomes useless.

If you live in a fringe FM area, the Grundig has terminals on the back for an FM dipole, as well as a DIN input/output jack and a headphone jack. The Partner has the latter two only. Note that the antenna terminals are only for FM and will not improve shortwave performance.

I have to say that I think Grundig's engineers got a little lazy on this one by providing themselves with tons of room to stuff their electronics into, while not taking advantage of it to enhance front-end performance. This radio suffers badly from cross-band interference. If you want a room-filling kitchen radio for FM, though, this one may fit the bill.

The big Boy needs big batteries : 6 'D' cells

NORDMENDE TRANSITA DELUXE

Radio makers tended to use the same model names over several years, while making significant design changes along the way. This is no different from the auto industry. A Toyota Camry, for instance, evolves in looks and features throughout the years. This applies to the Transita, the Telefunken Partner which I recently reviewed and probably every other radio produced in this era.

The Deluxe version of the Transita shown here was introduced in the early 60s, and is based on a wooden case covered with leatherette. This particular model covers the AM (medium wave) band, shortwave from 49m to 25m (~6-12 MHz) plus FM. The rounded profile gives it a charming retro shape. Later German radios became more squared off.

External connections include a Motorola automotive-type external antenna socket on the right hand side, and 9 Volt DC power input and headphone jack on the left. I didn't have much luck forcing a Motorola plug into the socket, because the chassis seems to be misaligned with the case.

A 6-cell C-size battery pack attaches with two snap connectors. As can be seen from the photo below, the back cover can be conveniently separated from the radio by unplugging the telescopic antenna's banana plug.


In this post, I will compare (subjectively) the Transita Deluxe with the Telefunken Partner 500.

I complained about the sticky tuning mechanism on the Partner. The Transita feels lovely and smooth in comparison. Despite that, on shortwave and AM, the Partner comes out somewhat ahead. The sensitivity (again, not measured, but subjective) is lacking on the Transita, as I found myself cranking the volume to near maximum when trying to find stations. Once I found a strong station, another Transita shortcoming appeared: apparent lack of automatic gain control (AGC). Because of this, I found myself jockeying the volume control every time I tuned in stations of varying strength.


From a sound quality standpoint, the Transita definitely was clean and generally sweet. The Partner, however, once again had the edge by offering more presence at the bass end. As opposed to the continuous tone control on the Partner, the Transita uses a switch, which introduces a single heavy-handed treble rolloff preset when pressed. I suppose a simple lower value capacitor swap in the tone circuit would improve it, but currently this is one feature I can't ever see using. 
 
The comparison of FM performance, however, was a little less black and white. While the Partner had apparently better sensitivity, in a crowded urban FM spectrum, this proved a slight disadvantage. I found the Partner subject to intermodulation (IM) distortion, which means it was overloaded with too many strong signals. This results in stations appearing like images in multiple places on the dial, and generally with distorted audio. This is different from the 'images' you would get on shortwave, because the higher I.F. stage frequency of 10.7 MHz on the FM band is generally effective at rejecting images. Retracting the telescopic antenna somewhat helped act as a front end attenuator, but then weaker stations get lost. By default then, the Transita makes a better big-city FM radio (sound quality aside), but the Partner would excel in rural fringe areas.

Performance aside, the wooden case and the retro curves make the Transita Deluxe a nice decorative element for any home with mid-century décor. While radio performance improved in later years, the plastic-fantastic housings they evolved into didn't carry quite the charm that this radio has.

TELEFUNKEN PARTNER 500

I bought this radio new in the late '70s. If you look it up on radiomuseum.org, it lists the country of manufacture as West Germany. Perhaps the version of this radio that was sold in Europe was made there, but mine (sold in North America and wired for 110V) was made in Taiwan. Given that it was made near the end of the '70s, it's probably safe to say that this timeframe marked the end of an era of great German-made radios.

Having said that, the design undoubtedly remained German. I still use this radio every day because the sound is what you would expect from a German radio - clear and full at the bass end.

All that despite the indignity it suffered when exposed one time to heat and smoke, as evidenced by the pictures. The grille is warped and the pushbuttons are a little wonky, but it continues to work fairly well regardless.

The downsides:

• Tuning mechanism is sticky, being plastic. I can't remember the reason, but I've had to restring it twice (arrrggghh!). Probably my fault, but it's now reluctant to go completely end to end. I may have wound something too tight, but don't want to touch it again.
• Switches - the bane of every radio. These are no exception. The heat may not have helped, but getting AM and long wave to work has been a struggle.

Features:

• Full North American FM coverage of 88-108 MHz (some European models only go to 104 MHz)
• Shortwave coverage of 19m to 49m continuous (~6 to 15MHz)
• AM coverage of 520 to 1600 kHz
• Long wave coverage of ~150 to 265 kHz
• Line input/output by 5-pin DIN connector
• Standard 1/8" mono headphone jack
• AM/Long Wave preset dial. I have modified mine to be a bandspread tuner for shortwave, but the idea is that you can pre-select a favourite AM or Long Wave station and go to that station by pressing the appropriate buttons on the top of the radio.
  

 

 Like most portables with a single wide coverage shortwave band, tuning in a station is fiddly and image rejection is typically poor. This is true of all single conversion receivers with a 455 kHz I.F., so no surprise.

 

I look forward to doing side-by-side comparisons with other vintage portables as they become available. I'll be comparing sound quality, sensitivity on all bands, the quality of the tuning mechanism, useability and overall build quality in subsequent posts.

 





Introduction

In this blog, I will be highlighting mostly portable radios built in Europe & Scandinavia during the 1960s and 1970s. These were referred to in Germany as "kofferradios" or suitcase radios because of their boxy designs and carrying handles.

Why these radios, and why from that era? First and foremost - big sound. The large size of these units meant that they could employ hefty speakers and provide a reasonable baffle for them. This resulted in sound that rivalled bookshelf speakers from that period. Kind of like a Bose tabletop radio before its time.

But there is another reason. At that time, shortwave was still a plentiful source of international and domestic broadcasts, so most radios had at least one shortwave band. FM was experiencing a swell of popularity, so it was included on most models too. And, of course, AM (or medium wave) was another band that was standard. Long wave, used mostly in UK and Europe but not North America can also be found on just about every model.

This combination of bands in one portable has disappeared in modern radios and mp3 players, so the kofferradios have become popular again for nostalgic reasons. Those features also make them collectible.

My interest at this time is only in transistorized radios. The intent is to show photographs of any radio that I can buy, borrow or restore that meets this criteria. Whenever I have researched radios online, I have often been disappointed by the lack of some of the most basic information a buyer would want, such as: what frequency range is covered on shortwave?; what is the shortwave performance like?; how good is the sound quality?; etc. I hope to remedy that in this blog by making those comparisons where appropriate. I will also stray from time to time and present European 'kitchen' radios and component receivers as they become available.

So here we go.......